Genki books are based very much on the Japanese system of drilling (over, and over, and over again). Which, given the percentage of Audio/Visual learners in the world, isn’t necessarily bad. The books are designed with a teacher in mind (not for self learning, although they can be used that way). In addition to conversation classes and language lab components that compliment the books.
If you’re just following the text - read each chapter three times. First, skim it/read it quickly. Second, read it through (light notations). Third, really read and dig in and take lots of notes. Do the examples along with the text.
You should also have the workbook for the text (green or orange, depending on if you have #1 or #2), which you should be doing after the third read-through (trying to do it without the aid of the text, but refer to the text as needed - making adjustments as you go).
Finally, it is expected that not only do you use the kanji and grammar of a given chapter, but also all previous kanji and grammar taught so that you can compose target sentences on your own (by way of a daily journal, writing practice, retention practice, etc).
It requires quite a bit of discipline to self-teach using books meant for the classroom. And you’ll not see improvement unless you work on both of each of the passive and active skills (listening/reading and speaking/writing).
(I did 2 years of Japanese study in university via those texts in the classroom).
PS: ALWAYS have a printed copy of Tae Kim’s Japanese on hand to leaf through!