Personally for me, what I did was talk about my idea with a cousin of mine. He got really interested in it and now we're working together on it. I would recommend talking to other people (your wife, your kids, your friends, etc) about your idea and see if you can get them excited. I did - and I got even more excited to hear their excitement.

Also, always try to set goals. Both long term and short term. When you see that you are achieving those short term goals, you'll feel like you've accomplished something and sooner or later, hopefully it'll snowball. Good luck!