The insert for our nappies are made of 2 layers each of bamboo & microfiber. First of all you need to wash the inserts. This gets rid of residue from the manufacturer and also helps absorbency. Simply put into your washing machine.
Tips: When the nappy is wet simply put it in an empty dry bucket until you are ready to do the next wash. If there is poo (which there will be hopefully!) rinse the excess into the toilet and pop into the dry bucket.
Washing: don't add fabric softeners just use something like Persil. Then rewash with other baby items. Its best to hang in the sunlight but if time is short dry on a medium heat in the dryer.