Start doing 500 words per chapter - you can do this by writing in word document in Times New Roman font, size 12. If you write 1 page, that's close enough.
When you feel comfortable with writing 2 pages of this, you're now near 1000 words - which is typically what I use.
When I first started out writing, I didn't do this so I ended up drying up and going months with writers block, because my 1 chapter was 12-16 pages long, so I wasn't ready to do the next chapter. Beginner's mistake on my part. I've never written before.
Also, you don't have to write all your chapters in a day.
You can plan some days for just planning the story and use other days to turn the planning into actual chapters.
Hope that helps :)