This book reminds me of Forest Gump's mother's description of a box of chocolates: you never know what you're going to get. As with any book you read, you will forget 90% within a week; 98% within a month. So, you want to know what you should concentrate on.
If you are in the corporate world, go to page 83: "What You Need to do if You Were Hired Today." Read to page 89. Then read it again. Then read it again. He offers 10 rules. All of them are good. If you systematically implement all of them, you will stand out as a contender. But Pareto's 20-80 law holds true here as elsewhere. You won't implement all of them. So, implement 20% of them. That means two. Which two? #4 and #10. (Buy the book to find out the 10 rules.)
If your marriage is in trouble, go to page 101: "25 Dates Until I Met Claudia." Read to page 106. There, he describes the post-divorce singles scene. I can think of nothing I have read recently that is more likely to motivate you to work on your marriage.
What about college? He says not to go. He explains why from page 37 to 48. I also say not to go. I earned a Ph.D. But I have a variation: earn a degree; just don't go. If you want my strategy, search for "college," $11," and "YouTube."
His section on keeping your mouth shut at dinner parties except for asking an occasional question is good advice. It begins on page 155 and goes to 158. This may be the most difficult advice to follow in the book.
If you want to write a book, read his section on self-publishing. It will save you a lot of grief. It will also get you published. It starts on page 91 and goes to page 96. His stories on how little money successful authors make by letting a conventional publisher publish the book should be required reading in every school of journalism and every course on creative writing. It begins on page 96 and goes to 101.
Cherry pick this book. Chocolate-covered, of course.