There are plenty of great methods to build strength with a kettlebell, but none surpasses the simplicity and effectiveness of the Russian Ladders.

Ladders allow you to build plenty of volume over time (the foundation of strength) without the side effects of hitting a plateau. It is reliable and foolproof.

Here's the simplest way using the Kettlebell Press as an example.
Use a mediumsize kettlebell you can press 610 times.

Start with (1,2,3) x 3 ladders for your first session. So press x1, rest, press x2, rest, then press x3. Do both arms obviously. Next session do (1,2,3) x 4. Continue along adding one ladder, training 3x per week, until you reach (1,2,3) x 10, for a total of 60 reps.

After that, start at (1,2,3,4) x 3 and progress to (1,2,3,4) x 6 over 12 weeks.

Finally, continue with (1,2,3,4,5) x 2 and build up to x4.

Start the cycle again with a heavier kettlebell.

This can take 68 weeks. If you are having a hard day, for example, and cannot finish your ladders, save it for the next session. Whatever you do, do not go to muscle failure. It will be counterproductive.