Many how-to books advise you to stride into a room and impress others with your qualities. (Para. 6)
Meaning: "Many books that offer advice on how to make a good impression tell you to walk into a room with quick, long steps and make others feel admiration and respect for your good qualities."
How-to books are books offering advice.
impress sb. with sth.: feel admiration and respect for sth.
She's always trying to impress people with her new clothes. 她總是試圖用穿新衣給人留下印象。
The same sentence can be rewritten with "make an impression":
She's always trying to make an impression on people with her new clothes. 她總是試圖用穿新衣給人留下印象。