You can use water, you have to put weeed in boiling water and leave it for a time, about 20 minutes to cook.
Eating raw weed does not work, whoever says that is living on a placebo. I can't smoke cos I have bad asthma so i know the ins and outs of eating cos I have been doing it for 3 years most days. The best quick way of doing it is hot chocolate made with milk, or pot noodle. Either way you will get fucked. If you eat raw weed you are wasting your money.