1. Be honest with your supervisors. Tell them you are panicking and you're about to fall into the black hole
before you fall into it. I cannot stress enough how important this is, they cannot help you if they don't know, once you are in there it is so hard to get back out. It also sets you back massively. I can't even begin to count how many times I emailed like 'hi I can't submit this chapter I need a few more weeks/days' and they had no idea I was struggling. Tell. Them. Now.
2. Try to write something every single day. Even if its like, one sentence. For me, the longer I spent away from my thesis crying, the more anxious I got about getting back to work. There was one time I had spent two weeks in bed crying with the stress of it, decided I had to start working again, sat down and opened my Word document and vomited. Write a tiny amount every single day, doesn't matter if you don't end up using it, just keep the momentum going as much as you possibly can. I actually did this even when I went on holiday but I was a very anxious student so I'm sure for lots of people this isn't necessary.
3. Ignore everyone else, don't even bother yourself with how far along they are compared to you etc etc. I spent so much of my PhD feeling like utter
tit because I was struggling, constantly behind, and it took me 4 years but you know what - I have
n e v e r been asked how long my PhD took, or how many corrections I needed. That one freaky genius you know who finishes in 2 years and 10 months has the same qualification as you even if it takes you 6 years and 6 months of major corrections. It does not matter at all. Same goes re comparing yourself with other people's publications and conferences etc - I only did 1 conference, and only published my first article in my fourth year. Yes I knew people who had like 4 papers out by the end of 3 years. Great for them! But not a reflection on me, nor you.
4. Work in whatever structure suits you best. I am naturally a night owl, I get up early now for work because I have to but when I was a student 4am was my bedtime. That's just my natural bodyclock, I work best at night and even now I do a lot of my substantive work late at night. Don't force yourself to work in a routine that you know doesn't suit you. I know people who swear by the advice that's like 'get up at 6am and write until midday' but honestly when I tried that I just sat crying for hours
again, you have to really ignore everyone else on that.
5. If you're doing empirical work keep notes on your methods as you go along because otherwise it's really hard to write your methods up later.
6. Same re referencing - it's a ballache, everyone says it and nobody does it, but do try your hardest to keep on top of it. If you're feeling very overwhelmed and paralysed, it's a good task to do because it feels productive and it has to be done but it's quite monotonous so very calming IMO.
7. My best tip and basically what pulled me out of the
tit pit - get a hobby that you can feel like you're progressing in and has NOTHING to do with your PhD. This was honestly transformative for me. It doesn't have to be something expensive or fancy. I took up something I'd wanted to do since I was a child and having set time in my week where it wasn't possible to think about my PhD because I had to focus on something else was invaluable. It's too easy to say you're 'having a break' watching TV and just sat there stressing. Force yourself to do something where its literally not possible to think about your PhD. It really helps you feel like you're achieving something else.
8. Similarly - maintain friendships with people who aren't on PhDs or academia. You might think it's easy for me to say as someone out the other side but genuinely - it is just a degree. Yes it is important. But it is not your whole life. It is not your worth or value. It ENDS and your life will go on. Keeping up relationships with people who aren't completely absorbed with academia and don't measure their self esteem by their academic work really keeps you grounded.