Worked from home for about 7 years ... at first this was a problem, but the biggest step you can take to solve this is getting an office space in your home, where the only thing you do there is work ... it helps a lot if it has doors that you can shut so that you can give yourself the mental feeling of 'going' to work.
The second thing you can do is have set hours ... doesn't mean you force yourself to be up at 9am ... but do make it regular, even if it is from 12pm to 3pm (or whatever) take it seriously. No TV (can't stress this enough), no running to the store, or the post office to take care of that quick thing.
Those two things really helped me a lot, hope it helps you out too.
The second thing you can do is have set hours ... doesn't mean you force yourself to be up at 9am ... but do make it regular, even if it is from 12pm to 3pm (or whatever) take it seriously. No TV (can't stress this enough), no running to the store, or the post office to take care of that quick thing.
Those two things really helped me a lot, hope it helps you out too.