Before learning to juggle with 4 clubs, it is essential that you can at least have a solid 3 club cascade pattern. This will get you used to juggling with clubs as well as getting the right spin, accuracy and timing. The other strong suggestion is that you learn to juggle with 4 balls, as this will help you get used to the pattern, the accuracy and the timing.
Double Spins: The first thing that needs worked on is being able to throw a club so it spins twice in the air before being caught again. When you are juggling with 4 clubs, every throw will be a double, so it may be worthwhile spending some time going through all the 3 club tricks you know and trying them out with double instead of single throws. This will give a whole new lease of life to your old tricks! It is worth noting that it is best to throw the club twice as high so that it spins at the same speed as with the single throw, rather than try to keep the same single club height and throw it twice as fast. It’s much safer, and also gives you more thinking time! You may find it easier to start with a normal cascade pattern then introduce one double spin, and build your way up from this, or just try from a 3 club start – the choice is yours, but it needs practiced lots and lots as it will affect every throw you make with your 4 club patterns!