Shift your perspective. 

Recognize that a new habit or routine does not happen overnight. You must view it as a process, rather than something that is just going to happen because you've decided to make it happen.

Plan before you begin.

Take time and write down you plan.  Make sure you think through the changes and adjustments you and those close to you will need to make to accommodate in order for the new habit/routine to work.

Start really small and keep it simple.

Pick one thing, like changing your diet. Take that idea and break it down into something even smaller, like adding more veggies to your diet. Break that idea down into adding a red or green veggie at lunch. Starting off with a really small habit will allow you to practice the method successfully before you take on more difficult habits.

Make it really easy.

When you first begin your new habit, begin doing your habit for 5 minutes only. Sticking to five minutes, even if you feel you could go longer, makes it so easy you won't feel resistant to doing it. Once you feel the habit is becoming automatic, then slowly increase your time.

Have accountability.

Create a daily system of reporting your progress to a family member, friend, online app, etc.

Have a support system.

This will keep you motivated and engaged in the work of your habit, especially if you start to get bored or tired of the work.

Reward yourself.

Decide what feels like a reward to you, and give that to yourself after your habit or routine. Change up the reward if it starts to feel rote.

Expect Setbacks.

Plan ahead for as many potential setbacks as you can and have a back-up plan. For the unexpected setbacks, just start again as soon as you can. Don't use setbacks as an excuse to stop your work.