Anyone else new to exercise?

I've done exercise before but I'm trying to stay with it. Right now i am walking for at least 30 min a day on the treadmill at a quick but comfortable pace for me (about 3.5-4) and I switch up the speeds so I might start out with 3.0 and then after about a lap go to 3.5 then to 4.0 and back down. Keeps it more interesting than just one speed.

Who else is trying to keep up with exercising and what do you do?