Learning martial arts requires a lot of hard training in different techniques, some of which are subtle (eg use of pressure points) and others that use nothing more than brute force. To become truly proficient, you will need to master a substantial number of these methods in order to give yourself options should the need to defend yourself arise.
Power training is one of the obvious methods in any fighting system; generally speaking, he who hits hardest eventually walks away victorious, assuming he can land any of those power punches on target. The mainstay equipment of most fighters is the ceiling mounted punchbag. These are heavy punchbags filled with rags. Aim to get one that is sturdy enough for kicking and knee strikes; you will get what you pay for with these. You may also opt for a punchbag that has a smooth surface, especially if you are going to train without boxing gloves – this allows you to practise open hand techniques such as palm strikes.
Speed and accuracy training is also critically important in the martial arts; having all the power in the world will be of no use if you never hit the target! An excellent piece of martial art equipment, devised for wing chun kung fu practitioners, is the so-called “wooden dummy”. The name pretty much sums it up; it is a wooden torso with arms and legs made of wood, jutting out at various heights. It enables you to practise close in hand-fighting, utilizing parrying, blocking and all manner of hand striking techniques. With the wooden legs you can practise footwork and low kicks.
For pure accuracy, you can try a home-made target; just cut a small piece of card to your required size (perhaps 2 x 2 inches). Hang it from the ceiling with a piece of string. This is great for practising jabs, fast snappy backfist strikes or finger jabs. And it’s a very inexpensive way to hone some of your techniques.
Ultimately, your best piece of training equipment is a skilled partner (suitably padded up if you are trying out power punching!) so the best advice I can give is for you to join a reputable martial arts school and get training the right way.