Top Ten Tips when you're struggling with your PhD

1. Get support
Get as much support from wherever you can.  This might be the University careers service, counselling service, equalities service.  It could be your friends (from outside academia), perhaps they have skills which you can tap into free of charge, help with time management for example or motivation.  Your colleague PhD students will be of enormous help - can they read what you've written?  Can you get an academic or non-academic mentor?  Do you need to re prioritise if other stuff is going on?  Talking to friends and family can help you do this.
2.  Ask for time off
Have you had any holiday recently?  Are you ill and need to take sick leave?  A bit of 'me-time' might be all it takes to get back into the rhythm of writing again.
3. Take time out for thinking
Very important that you allow yourself time to think about things, this can sometimes take weeks. 
4.  Ask for what you need
Look again at your training plan.  Have you understood and taken on board all the training you have done?  Do you need to go on some of the training again?  Do you need to attend new courses?
5.  Listen to and act on feedback
If your supervisor has asked to to rewrite something think carefully about their comments and try to incorporate their thinking - after all they are more experienced than you.  If more than two people have said the same thing to you - like 'have you contacted the University counselling service?' then chances are it might be a good idea to do just that.
6. Write as you go along
There are a lot of blogs and help online for example #phdchat on twitter and thethesiswhisper.com. Perhaps set up your own blog and document your thinking, even if it's quite unsure, documenting it might illuminate new avenues. 
7. Do something else
Focus on another part of your PhD for a while, perhaps an area where you're stronger.  You might have to do something completely different, perhaps join a friend for a badminton, tennis or cycling outing.
8. Read your favourite inspirational texts or books on the topic
To help motivate you at this difficult time.
9. Read how to write books or draw a mind map
Authors like Patrick Dunleavy, Roweena Murray or Tony Buzan might help.
10. Stick up to your supervisor