Yeah, I was the same. I also spent most of my Year 10 holidays just watching TV, going out with friends etc. I only really started revising about two weeks before the exams.
The advice I can give is that you can start waking up a bit early such as 6am. Then, have breakfast, shower etc. until 7am, and start revising.
Make a habit of doing about 3 or 4 subjects a day. For example, you can learn 10 words in German, and then do one topic for maths, bio, chem, physics and geography in the morning.
After that, take the afternoon off to do whatever you want, and return in the evening for about 2 hours before bed to read through your notes.
This way, you'll have your afternoon to look forwards to, and you'll be a lot ahead.
I wished I'd done this because last minute revision was horrible. I used to get 5 hours of sleep during exams sometimes and even less when the exam was the next day, and I hadn't even opened the book. It was really stressful, so maybe you can use this as motivation to not do the same.