To learn how to do something, make it as easy as possible for yourself. When it becomes so easy that you become bored with it, you will naturally want to increase the intensity. If you let the natural learning process proceed in this way, your skill will progress automatically, without any conscious striving. In tai chi this is codified as the 70% rule: when practicing tai chi, exert at no more than 70% of your maximum capacity.
To speed up, slow down.