Small steps to increase the will power:
1. Be regular and punctual at work. Fix a time for sleep and waking upas well as for exercise and follow it religiously.
2. Step back before speaking. Try reflecting upon what one is going to speak or write.
3. Not to act under an impulse but only after careful consideration.
4. Delay gratifications in matters of eating.
In general any kind of self control helps strengthen the will.