Okeee so I don`t do sociology alevel but I can give you a plan to self teach yourself bcs that`s kinda what I`m doing since most of my teachers can`t teach.
Step 1: seriously, don`t think of it as a screw up. You honestly are NOT in as bad a situation as you think bcs I have to do the same thing and five months is more than enough time
Your mindset/attitude has a massive role in this.
Step 2: now that step 1 is out of the way, make a timetable of what topics you`re going to cover on each week. Be realistic but make sure you finish studying the topics and understand them THOROUGHLY. Research your spec online and make notes on each of the topics. Write essays for the topics and sit past papers after you`ve learnt all the content
Step 3: If you really don`t understand a concept, troubleshoot immediately because it can deffo build up. Maybe speak to a school sociology teacher and try to get them to explain it? If the teachers aren`t good enough, try to research it yourself but whatever you do, make sure you don`t leave out topics (pretty obvious but its easy to get sidetracked with these things)
Tbh the most important thing is that you plan a realistic timetable that you can stick to and focus on getting quality revision. You can revise for a solid hour and completely understand a concept or something or you can get 5 hours of "revision" without really getting anything done.
Speaking of getting things done, what works for me is not to focus on getting physical things done with revision (haha) but rather trying to get it into my brain. I`m not gonna have notes in the exam, I`ll only have my brain so its no use making notes if it doesnt get the info into my brain.
I hope I helped despite not doing sociology