Hi Konstantin,
- 1m is a good length. Most people use around 1m for staff juggling (usually a little shorter).
- I don't know who started 3-staff but it was Antti and Tommi (The Amazing Rubberheart Duo) who popularized it. Unfortunately their website has gone now as they no longer perform together but their videos are on YouTube.
- I guess the easiest way to understand the "31, 41" stuff - if you're interested - is to learn the 'juggler's language' which is called Siteswap. I made a post earlier on this thread with some links that will help. Before anyone else says it, I feel that it's important to let you know that siteswap is just one way to describe juggling patterns and that if you actually want to learn the patterns that are described by the numbers, the best way is to have someone teach you / watch a video etc. However, very few (maybe 0) teaching videos exist for staff juggling at the moment, so you will probably have to figure out some patterns for yourself.
If you have a specific request for a video tutorial for a pattern (that I can do!), ask me and I'll see if I can help.
p.s. people normally reply to posts here more quickly, but the festival season has started so a lot of people are in fields at the moment

Hope that helps
