How often should I practice typing exercises?
As with anything, regularity is the key to success. Strengthening muscle memory takes a lot of practice, and it is important that you exercise regularly.
Exercising 15-30 minutes daily will be more helpful than two-hour workouts once a week. It is easier to maintain concentration during short exercises, as well as being much easier to carve out time for them.
Practice whenever possible and not just with the Ratatype. Try to practice your touch typing skills while communicating on social media or when performing less urgent work tasks.
Typing test is also a practice. Take the test from time to time to see how much your speed has improved.