Working on getting more sets of 10 of the 24kg one handed into my working into Simple. That's not been too bad, the hard part was getting to the 10 reps in a single set.
I tried a number of things in the name of experimentation, and it took me about a good 4-5 months to get a good strong set of 10 on each side where I could snap the bell to chest height and feel confident in my grip throughout a set. What ended up in the end working well (for me, at least, your case may be different), was to swing the 24kg two handed for all 10 sets, to the point I felt fatigue /breathing was not as much a limiting factor with this new weight, and I could generate some power (that took several weeks). I then endeavored to add one handed swings by starting the first two or even three reps of a single set two handed , to get the groove and feeling (and confidence) and then take my hand off the bell at the top, allow the backswing (one handed) bring the bell back up to the top (one handed) and get free hand back on the bell, a swing (complete back and up swing two handed), at the top take the other hand off and do a swing one handed, and so on.
At first I was only able to do one rep per side (especially my left, I am right handed and even though have had a right hand injury), then eventually two or three at a time, etc. I did work with trying some pre planning in that I was going to bump up to "x" reps per hand with each set/session, but the in the end what felt better was to take an overall more fluid organic approach and literally take it analyzing rep by rep in a practice with no preplanning from workout to workout...if I felt my grip was weakening or I was shoulder shrugging or muscling with my arm, I would do a few two handed and switch to the other hand (provided my hip snap or lungs were still good). I liked this way too as it felt like I could get some lighter days in there...some days were stronger than others depending on recovery and I was not forcing myself to do a set of 6 on each side one handed in my set of 10 when I really may not have had full capacity that day, I could work with my fatigue, recovery levels, etc.
Eventually I was able to get full sets of 10 and have kept the use of the 24 at that, although I am using the 20kg for some sets as well at the moment and adding a set of the 24 every couple sessions.
Like others have said, it's a process. Be patient, you can do this.
Show that bell you are the boss of it!