Lead by example is one of the best way to influence people. By your acts, do your best. Do your best is not a sacrifice for anyone. Do your best is for yourself, for the better of yourself. You deserve to be good and to be better day after day. It is your responsibility towards yourself to be good.
But to influence people, lead by example ONLY is not enough. It should be combined with other approaches. Otherwise people could abuse you and expect you do your best for them freely and in long terms the situation will worsen, however good you are, however good as an example you are.
It should be a combination of the following steps/approaches:
1. Define the reason why you need to influence people. Is it better for them to think as themselves? Or is it something very important that you need them to think and act as you would like? If it is the second then try the bullets below.
2. Lead by example. By your acts, do your best. Do your best is not a sacrifice for anyone, do your best is for yourself, for the better of yourself. You deserve to be good and to be better day after day. It is your responsibility towards yourself.
3. Influence people by what you speak to them: gradually, every day, softly but firmly, never over-expect that they would listen and follow you (at least first time). People will tend to react and go against you, you should accept that. Never lose your calmness, don’t over-egg on emotions, it simply does not work. The more you over-expect that people listen to you, the more they contradict you. The more sentiment (sadness, anger) you put in, the more the chance people will make you feel more angry and sad. So be self controlled.
Be firm and disciplined and be serious on what and how you talk, speak, write.
4. Have a way to implement discipline or punishment. It can be small things, but be assured that you have a wide range of tools to do that. Otherwise you don’t have any power and attempt to influence people is useless. However the discipline/punishment, apply it with calm, correctness.
5. Can accompany discipline/punishment with love, caring. You would like to influence people because you love and care for them, not to destroy them.
6. Have ways to measure your success. If you do your best but still unsuccessful then you have to learn to accept.