Nothing too exciting though, just another step on the ladder.
You should not be setting your ladder steps at round numbers, and without getting too caught up in the placement of the orders of other people, of course, you do want to attempt to front-run any order placement locations that might have a lot of resistance/support and therefore even having a decent cushion between your set order and the likely resistance and support points .. some of those resistance / support points are going to be more obvious than others, and other resistance / support points might only develop after you had already placed your orders.
By the way, usually, I personally, don't really monitor or second-guess my ladder orders once I place them. Except the overall caveat above regarding round numbers and anticipated resistance/support points, I largely place my ladder orders in accordance with my own measurements and preferences rather than giving too many shits about what others might be doing or how they might be changing their orders at specific locations after I had already placed my orders... but hey, I am not saying that there might NOT be some learning involved in such monitoring of how orders are placed and being placed by others and maybe from time to time you might be able to increase the likelihood of your order(s) filling before the price reverses (which tends to be a goal of laddering). Nonetheless, having said all of that, after you have kind of learned some various strategies, I tend to find it a bit of a waste of time to dicker around very much with my orders or even to monitor how close they are being filled by the behaviors of others, once I have placed my orders.. either they fill or they don't fill.. and once they fill, then I can place the order(s) of the opposite direction.
Never put anything past the picnic bear.