I have a yearly mileage goal and a number of commuting days goal. I also work on my time to get the best times I can. I record all this in my bicycling journal. I put my mileage up in my cube at work as I hit milestones along the way. I also plan multiple century rides so I need to get the riding in 4 to 6 times a week to pull it all off. It's toughest in the winter though. I also subscribe to Bicycling Magazine and I can't wait for each new issue to come out. I weigh myself and I know I need to ride frequently and hard so I don't go back to what I used to weigh.
Keep your bicycle in front of you a lot. Make plans and do them. It's worth it.