A kickboard is great to isolate the legs while giving the arms a rest. It also keeps your head out of the water for unlimited breathing. You can do a freestyle kick, breast stroke kick, or butterfly kick; the latter two are frustrating to learn, but satisfying once you get it. Try not to lean on the board with head high and legs low. Let your chest drop low into the water so legs come up near horizontal. Eventually you should be able to do the same kicking without the board.
Pull buoys come in a few different styles, but they all serve the same purpose in giving your lower body more float and stopping your kick. The idea is to just pull with your arms with legs following quietly behind you. Pull buoys help new swimmers get a feel for good horizontal body position. A few swimmers with a great kick will go slower with a pull buoy, but most will go faster because of the better position. It’s almost like swimming in a wetsuit.
Fins also come in many sizes and are the most overused pool tool since they take the wirk out of swimming. Fins slow down your kick, but give you much more propulsion with each beat. Small fins are best for serious swimmers as it keeps your cadence closer to normal for no fins. A benefit of fins is that they help improve ankle flexibility. Without fins swimmers who can’t point their toes are at a big disadvantage. Over time fins will help stretch the tendons across the front of your ankles so you can point your toes.
Paddles increase the size of your hand, and magnify any flaws on your stoke. They come in many shapes and sizes and all slow down your turnover so you’ll get down the pool in fewer strokes. Fewer strokes per length means more power output for each stroke cycle. The effect is similar to weight training or intentionally over-gearing on the bike. the important benefit of paddles is not more power output per stroke, but the increased feel for holding the water effectively through the whole pull and push. ***Beware, swimmers who have a poor catch where they push down at the beginning of the stroke instead of pulling back are at real risk for potential shoulder injury with paddles. Make sure you do not use too large of paddles. Unless you have your own, paddles are used under coach guidance.
A simple strap to bind your ankles together is another great pool tool. It’s incredibly frustrating when you can’t kick at all and your legs sink! The band forces you to get a feel for optimal body position with chest and head low so legs come up. You’ll have to maintain your speed with the band or legs will sink to the bottom very quickly.