Treadmills seem pretty self-explanatory, right? Maybe. But they may also have features that you aren't using. Don't forget, features or not, you can always change things up just like you would if you were walking outside. In fact, it is important to try and keep challenging yourself and to keep things interesting on the treadmill so you don't get bored with it. Walking is one of the best low impact exercises you can do. Don't end up giving up on it because you didn't add enough variety.
Determine what your goal is for your treadmill. Are you trying to slim down, bulk up, or a bit of both? When it comes to your treadmill, the answer to this question matters. To slim down, walk a bit faster, with longer strides. Taking long strides helps keep your muscles supple while the pace will help burn fat. To bulk up, slow things down, but consider using the incline feature. If you don't have an incline feature, add weights to your legs.
When you set goals, they need to be measurable whether they apply to working out or not. This is true of using your treadmill as well. If you are walking at the same pace every day, set a time to beat or meet, or measure your steps and/or distance and set goals each week. You can also change the speed of your walk or jog and keep the time the same. Try to work up to a feasible speed, but don't go so fast that it is dangerous for you.
Even if you aren't trying to bulk up, weights can be beneficial on a treadmill. Consider using ankle weights one day, small dumb bells the next. You might even use weights on your thighs. Whatever you choose, try to change things up through the week so that you aren't using the same weights in the same places every day.
Do what you can to make the experience more enjoyable. Play music while you walk or jog. Watch your favorite television show so that you make sure to work out at the same time every day. Don't forget about your arms either! You can work on balance and weight loss or strength training by wearing arm weights or using dumb bells on the treadmill. Just be sure you are comfortable enough on it to do so at a safe speed. Adding this variety will make your workout more enjoyable.