Indeed it can be overwhelming. When I was first learning TI I made a long list of all the focal points. Believe me, it was a very long list! I wanted to get through all of them as quickly as possible. I would focus on that single focal point until I felt I had achieved competence then move to the next one. I got through some FPs in a few seconds and others are still on my list. I soon learned that only a few focal points were meaningful to me. I revisit those often, usually not more than 3 in a single workout session.
I have come to realize that my "list" is infinite. There are always new FP's to add in order to refine this move or that one. Accepting this as an ongoing task has allowed me to slow down and enjoy the exploration more- no more rushing through lists.
I hope this helps.
I always have a few FP's with me when I go to the pool. Then I let the process take me where it will. Holding on to one FP at a time is hard work but you must do the hard work to create connections in the brain. Make the repeats short. When you get bored or tired, use another FP for awhile. You can combine 2 ( even laps and odd laps) but that is about as much as my brain can manage.