The siphon is recommended to transfer the fermented liquid (mash) into the boiler of your still. Just pouring the entire content of the fermenter into the boiler is possible, but you will get all the dead yeast sediment into the boiler as well. During the distillation, this will give a nasty flavor to your alcohol. Therefore it is recommended to transfer the clear wash only! That's why you need to use a siphon..You can use either a garden hose or go for the more advanced solutions which will cost you a few $.
The pictures below are a few examples of siphons which are sold through the regular homebrew retailers.