The key is to not use the wrong muscles to press into the bow. That is what I’m always trying to explain in my lessons. Here are the muscles/concepts that cause a bounce if you use them to press into the bow:
Grabbing the bow tight to achieve bow weight
Thumb/pinky stiff to aid in pressing
The key is to use the index finger while all the other muscles are relaxed. If you are doing this properly, you can actually press into the bow quite aggressively and not get a bow bounce or squeak. In bow physics terms, you need the bow to be as flexible as possible as you press into the strings. If you are using the index but the bow is stiff, then it won’t do what you want it to do. Each of these points are equally important.
Check out these videos to further understand this concept.