Assistance
AI
You can follow this guide to subverting the AI.
Cyborgs
Emagging cyborgs is also a very efficient way of getting friends. Simply tempt a cyborg with a better cell or a radio key and they will open up widely for you and let you swipe your emag on them with no risk of being outed.
Crewmembers
Simply asking and talking to crewmembers might help you more than you think. Ask the chemist for some funny grenade. Hell, ask them for something seemingly innocent even. Could be asking for pure meth in order to get high, only to use its explosive properties. Although, a good chemist will most likely wait till late-game to do those orders. Having a pile of cash would help with a lot of issues too. Ask them a bit sneakily if they are morally flexible. I’ve given a dude 200 units of pure meth for a sum of money, think he was going to use it for himself. Nope, he blew up a Security Officer. lol
Stealth
Do Your Job
Simply doing your job will make people comfortable with you. If you do your job and do it well, communicating a lot and so on you can very easily become acting Head of Staff or even get extra access. All you need is a justification. Want Science access? Ask for Exploration access saying you want to help the Explorers or say that you want to experiment with Xenoarch. Asking for things directly is not ideal as it makes it very obvious what your intentions are. If you want chemistry access, PDA message the AI to open tech storage and make your own meth lab somewhere else. Parts you can ask for in Engineering or Science or print them at an autolathe as a last resort.
Telecomms
A very simple method of being outed as an antagonist is yelling for help via comms. However, hacking comms is very easy to do. All you need is two remote signalers, some generic tools and insuls. Now get yourself inside telecomms. You could ask the AI to let you in to get a link for the Exploration shuttle or other telecomms system. Alternatively ask for Engineering access or hack yourself in. What you are looking for is the APC inside telecomms (not the one in the control room). Now you want to find the wire which controls the power. Once you find it with a multitool you want to cut it and mend it quickly to ensure no one notices comms going down. Install the remote signaler on the power wire and close it all up nicely. Now you have a remote way of instantly disabling telecomms and no one will know. AI might notice it on stations like Meta Station where the AI is right next to it while Box is probably the easiest one to get into. Send a pulse with the remote signaler and telecomms will be off for a few seconds, letting you do whatever you want for that time!!
Chameleon Kit
The power of the chameleon kit is immense. Do not underestimate it. I’ve subverted command, been outed as a changeling, thrown off Security just one door away, and all that for 4 TC (including the Agent ID)! Whenever you want something. Locate the general location or task of a head of staff, then disguise yourself as them. You will need to do some extra work in order to sell it well, get the coat, beret and so on. Ensure you got the mask too so you sound exactly like them! You can sell it extra well by using a fake stamp and some simple paper work. The more you make it look legitimate, the easier people will fall for it and not cheese it like double checking via comms.