Affirmations like this are a good way.
You affirm it to yourself immediately after you wake up in the morning.
If you are doing a difficult stuff, you can affirm at that time too. Like brushing your teeth with the non dominant hand or exercising.
Keep doing the difficult stuff (where you have to pay attention) and at the same time affirm whatever it is for you.
Another thing, remember that it will take time. It won’t happen immediately. I’m on the same path.