You are the Head of Personnel. Your main responsibility is to sit in your office and listen to people request access to X area or ask for Y job. You are also in charge of making sure the Quartermaster is managing the supply sector well and that each civil department is working. Should the worst come to pass, as well, you will need to assume command of the station as acting Captain.
Bare minimum requirements: Stay at your desk for the first 10 minutes, and don't wander off far.
Your primary purpose is to sit at your desk and process people's requests for access. People often wish to change jobs, or require additional access in order to do their job more effectively (or further their dirty Syndicate goals). It's also your responsibility to wipe access from the IDs of troublemakers at the request of other heads.
There are two ways to alter access. On the bottom of the ID console screen, after logging in, there is a list of accesses you can click to grant to or remove from an ID. These are usually access to specific areas of the station, but they may also affect one's ability to use certain ID-locked machines. You can also assign someone directly to a job by clicking “Show” under Assignment; this will bring up a list of potential jobs you can click to assign an ID to as well as a “Custom” option, which is useful for HoPs who want to give crew members special titles, or traitors who want their all-access ID to read “Assistant.”
People will come to you with requests ranging from outlandish to mundane, so use your brain, and ask a Head over the command channel for any objections before assigning someone to their department. Note that you will be held accountable if you give out access to a department without authorization from its head. Use common sense: maintenance access isn't a big deal, access to toxins is.
If you repeatedly ignore other heads of staff, adding people to departments randomly or handing out all access like candy, you can and likely will be contacted by an admin. Repeatedly handing out access to others in a way that causes problems for the ship will result in you losing the ability to play as the Head of Personnel, so be mindful of what you do with that access computer.
If you plan to make yourself an all-access Hero the Station Deserves, bear in mind that access is not equivalent to permission, and security will arrest you and throw you in the Brig or the Captain may demote you if you're seen waltzing into high security areas you're not supposed to be in. Talk to the head of the department you're visiting, and ask before taking anything valuable.
Your ID console has the ability to open and close slots for the majority of jobs. This is useful for situations where no more positions remain available, and helps greatly to stem the sudden influx of 20+ assistants clamoring for access. This is also a good tool to use when somebody who has taken a valuable job is either dead, demoted, traitorous, or an all-around useless chucklefuck.
If you're feeling creative, make up your own jobs with custom titles and access levels. There's a world of fun gimmicks you can play around with.
You're supposed to be in charge of the civilian and supply departments. Nobody in these departments is going to listen to whatever stupid orders you give, but feel free to befriend the quartermaster by opening secure crates for them, smoke weed with the botanists, or take a relaxing break on the mining base.
If the real Captain is KIA, MIA, or simply never arrives, the Chain of Command drifts to the Commander, then the Executive Officer, then you. If this is the case at the start of the round, it is typically wise to make your first order of business the securing of the important items inside the Captain's Quarters: The Captain's Spare ID, the Nuclear Authentication Disk, and the corresponding Pinpointer. Picking up the Hand Teleporter never hurt anybody as well, considering it makes for a powerful escape tool in emergency situations. Do not forget that you will, in fact, need to up your access (Preferably to Captain levels) to do so. The Pinpointer is often best left in the hands of the Head of Security or the Warden, so that they can find your battered corpse or the perpetrator of your murder… or track you down, if you give them reason.
Don't take too long to secure the Captain's items, or else either the Head of Security or some Assistant will take the mandate of Acting Captain upon themselves. Either way its a fight you'll have a hard time winning.
Due to your low workload compared to other heads, it's a good idea to always pay attention to general radio. People will often try to use this to summon you to your office when they need an ID upgrade. Aside from that it never hurts to have an awareness of what's going on around the station. Chat with the crew so they know you're not the stereotypical helmeted all-access mute that has come to epitomize the position.
When Revolution abounds, you will be one of the more well armed and threatening heads. A tendency for disappearing acts makes the Head of Personnel usually the hardest head to kill.
You first move should be to deconstruct your ID console and reassemble it somewhere more secure (probably security). Leave an ID computer ID in it so security officers, heads and the implanted can give themselves all-access.
If shit hits the fan and you need to hide, pick a job where it's natural to be wearing a mask that hides your face. Scientist, engineer, mime and clown are all good examples. Make yourself a Captain ID with that job title and a false name. Travel to where the equipment lockers for that job are kept, and get dressed. Put your old clothes and equipment in your old backpack and put it into the locker, locking it after you're finished. If you leave your Head of Personnel's jumpsuit lying beside an open Engineer locker, anyone who sees it will figure out what you're disguised as. If you want to be an even more stealthy HoP, head to genetics and turn a monkey into a human. Proceed to stab yourself with the UI+UE of said monkey. Then just go and use your ID console to get an all access ID with your new name on it.
If you're the last remaining head, in the interest of fair play, you should try to escape the z-level instead of extending the round for your own benefit at the expense of all the dead people stuck sitting out. This will cause the revolutionaries to win, but you will survive. Self-preservation is a valid reason for ending the round. Or say to hell with it, grab the nearest blunt object or gun and go out in a blaze of glory.
You have the ability to mass produce all-access IDs, and you do not start the round loyalty implanted. As a result of this, you are a prime target for conversion. As soon as you hear that a gang has been discovered, move your ID console to security and get yourself implanted, assuming security hasn't been made an offer they can't refuse.
It is in your best interest to cooperate with security early on, as Gangs tend to bring out the worst in security, and being on their side early on can spare you a lot of pain later on. Unless of course you've already pledged your allegiance to a gang.
Similarly to Gangs, the Head of Personnel has the third ID that can be used to manage access levels for ID cards. Picture the biggest set of crosshairs you can imagine, and then picture them on your back. Get the hell outta dodge as soon as you can.
As a fail-safe, you can remove your own ID console access after granting it to a special blank card. This should slow people down who attempt to use your stolen ID to hand out all-access.
A good tactic is to have three ID cards on you. One ID is you general ID card (but with ID Console access removed), a second blank card is your hidden all access ID card (with ID Console access removed), and the final card is you actual ID Console access card. Hide or place your two special access cards somewhere (one of your ID Card boxes helps) and shuffle the deck. This will make it extremely hard for anyone who killed you to figure out which card is the all access.
Short of a Chief Engineer tasked with stealing his own blueprints, traitor HoP is the easiest traitor job on the station. Give yourself all-access, use cargo for free guns, try to become acting captain and turn the station into your personal playground of terror. You can do a few fun things.