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Creating good habits can be as tough as breaking bad habits. From my experience, one of the most important factors         make forming a new habit hard is that a lot of willpower           (require), at least in the beginning, and that alone can prevent many people correctly developing their desired habits.
Now instead of just using willpower and reminding          (you) to start the new habit each day, why don’t you just link it to an existing one? I have done          experience. It started with just 20 pushups (俯卧撑), something easy. So before I showered each day, I would do the pushups.        a couple of days, I increased the amount just to make it a bit more challenging.
Gradually, over the course of about 3 months, I’m now doing 100 pushups. And as the habit grew stronger, it got easier to do so          (natural). Now I know the habit is pretty much ingrained (根深蒂固), for I feel like something is missing         I don’t do this before showering. I found it pretty easy         (create) this habit and not much willpower was involved.
I think the key, apart from using an         (exist) habit, is to start out with something really easy. Once that starts becoming part of your     (day) routine, add on to it.