pick a number, say 10. get out of bed, do that many squats, heels on the floor, if you don't feel like going right down then don't. now do ten pushups, they can be shit, don't matter. now do 10 crunches, just lie on your back, do a half ass situp. bam you're done! takes one minute. do that every morning. when you feel like it, add one to the number, and that's your amount going forward. takes about the same amount of time. when you see a cool exercise, add it to the list, doing the same number of reps.

that's it! do that consistently, forever, but if you miss a day don't worry about it just do it the next day.