Comment by nickcw

I always felt that 4 wasn't a huge step up from 3 for most people, especially given the right tips. If you learn 3 in a day or two then 4 is a week or two. That kind of thing.

A good trick to practice 4 is to throw 4 throws in the middle of 3. So you juggle 3 balls then throw one to the same hand (the 4 throws) while holding a ball in the other for a beat (the 2 throws). You can put the 42 throws anywhere in the 3 pattern and if you do it as quickly as possible you get 423 which is an interesting pattern. 441 is good too - harder but helps with that sync problem.

The big step comes at 5. It took me nearly a year to master 5 balls with consistent practice. I eventually got reasonably good at 6 balls (juggled in sync, crossing over) but that's where I plateaued as far as numbers go.

There are lots of other things than numbers though. Non jugglers will have no idea how many balls you are juggling so you can impress with 3 balls. My favourite party trick was blindfold juggling. I used to be able to juggle 3 balls for about a minute like that.