I must say that it is hard to stay motivated. But I manage to set a schedule and stick to it. If for some reason my schedule gets altered and it affects my workout schedule, I choose another time or find another means of exercise (bowling, swimming, walking). Sometimes I even do a little at home.

Try making your workout fun. If you have a gaming system (like PS3 or Xbox) you can get their Zumba, Just Dance, Sports, or MJ Experience games. Those are really fun. I'm thinking about hosting a Get Fit: Games party for my friends and I.

My main suggestion is to not think about it...just do it! Once you start thinking, you tend to lose motivation...at least I do.

I found that by adding exercise and active items throughout my day it helps me to stay motivated for when I do workout. For example: using the stairs vs an elevator, mixing something by hand vs a blender/mixer. I also found that instead of asking someone to get something for me I get up and do it myself. I go and get the mail or I go and get myself a glass of water. Anything that I can do to stay active. Then when it is time to workout I have already been moving all day and it helps. I also found that by having someone else hold me accountable is a great way to remind myself too. When I am having a hard time getting a workout in, I have my sister-in-law call me in the morning and hound me till I have the motivation to go and workout.
Another thing that has really helped is just working out enough so that I feel a workout and then stop. If I workout too much, I have no energy or strength to continue to workout the next day. I tried one of the P90X workouts for the first time and I was unable to workout for the next 2 days because I was in to much pain. So by remembering to not push myself to far, I can continue to workout each day.
And schedule it and stick with the time block that you made. Once I had my workout as a daily thing it because so much easier to do it everyday. Think about it... what do you do every morning when you get up? Do you have to remind yourself to do these things or are they now a habit? It takes 4 weeks to make a habit and 12 weeks to break one. So by making it part of your schedule, it won't be something that you have to tell yourself to do, it will come naturally.
Also, mix it up. If you had to sit on a bike for 30 mins every day, every week, every month. It's going to get boring and you are not going to want to do it anymore. Plus you are no longer pushing yourself if you are doing the same thing all the time.

I stay motivated by thinking of the clothes I'll be able to wear when I am smaller. I think about if I want to go out and dance, I wouldn't feel so self concious,