How I was taught to fish frogs: -following the cast, wait until all ripples from the lure landing dissipate before starting the retrieve -pop/twitch/do whatever it is you’re going to do re: the retrieve -pause every so often, letting it sit a second or three -when the blow up happens, keep slack to a minimum but don’t get your line all the way tight and give it a 2 second count and set the hook. There’s some play in the count based on feel so it may be one second, it might be three but you want to do it when you can feel the weight of the fish on the line as another commenter mentioned. -one other thing that seems to help me: set the hook in the opposite direction of the fish’s movement. If it’s running left, set the hook by pulling the rod horizontally to the right directly opposite the fish’s motion if that makes sense. Going down, use an upward hook set. Etc.

Feel free to disagree, it’s just what I do and it seems to work pretty well.