1) This http://www.youtube.com/watch?v=KGg1567fzTY (almost posted anonymously). Deal with it :)
2) If you have a family or a partner. Just because you are at home does not mean "can you just put on a wash". Build rules into engaging with the family. You are working. You are not to be disturbed. If you choose to 'come out' of your office and engage with the family then that is your choice. Emergencies are acceptable interruptions ;)
3) Make an office. The kitchen table is not a great space. A spare room, an office in the garden. Some place where you can just be professional. Avoid having the office in your bedroom. You need a room you can lock.
4) Exercise. Seriously this is huge. Too easy to slob out. If you get up and work at 6am, then go to the gym at 9. Do something. Make sure people you work with KNOW this is your routine. Make it a routine. Get out of the house and do something. Do not buy an exercise machine and stay locked in the house. Clear your mind, stay fit, and go out and see the world around you. Don't like Gyms? Go running, swimming or, my favourite, cycling (it clears the mind and you can easily cover 10 miles while solving a difficult problem).
5) Get a dog :) Best decision I ever made. Get's you out and walking. You meet other people and mine keeps my feet warm. Oh and she's very good at solving technical issues. Sounds mad, but sometimes just talking about a problem to her makes it work for me (and makes me look less stupid when I have to discuss the problem with work colleagues).
6) Eat well. You have the time to make great food. Use it. Learn to cook great food.
7) Pomodoro method. Some like it some don't. (I'm not a fan.) I prefer things like coffitivity. If things start going south, try it. It's a decent rule system.
8) Skype. If there is a group of you working together, just skype each other and carry on working.
9) Socialise. Suddenly this is huge. Find local interest groups. Go to meetups. Get involved. You won't realise it, but you can get your head down and 3 months later you haven't seen anyone recently, cos y'know, work. Join clubs. Do stuff. Give yourself a reason to not be working in the evenings.
10) Monthly team days. Once a month get together and have a hackathon. Go get drunk. Be a team.
11) Use trello. I mean REALLY use it. A complicated example here http://community.uservoice.com/blog/trello-google-docs-produ... but build your own work flows that work with your team. Don't be afraid to tear down your process and start again AND most importantly, EVERYBODY buys in. Don't be the only person using a project tool. You will fail.
12) If you end up doing a 16 hour day, recognise you've done two days work. Have a reward. Go see a museum. Have a long lie in. Finish early and go for a ride. See (1) ;).
13) Have fun. Be comfortable in working on your own. Give it 6 months. See how it feels. Don't like it, then move on.
14) I may have mentioned this...exercise. Get out and do some every day. No excuse.
15) Requirements management. It's a pain to do, but clients try and be sneaky. Avoid fixed price unless you KNOW exactly what it is they want. Most don't and even those that do, change their minds. Your fixed price contract MUST include a change in requirements clause and what happens when they do. You will invoke it.
16) If your client is haggling over local sales tax....walk away. Imagine the pain you will go through haggling over signing each feature off.
17) Have payment milestones.
Right must go walk the dog :)