Okay....the hash oil techniques given so far are crap.....Here is a recipe fro honey hash oil that is simple to make but needs a lot of patience.
1. Get a shitload of trimmings (eg, tip leaves, shade leaves, crappy little kiff buds, etc)
2. Put your trimmings in a large pot
3. Get a bottle of 100% ethanol (Metho works just as well)
4. Soak the trimmings evenly with the ethanol and let it sit for about 15 minutes
5. Once you have let it sit, pour boiling water in the pot (fill er up) and boil for about 4-5 hours...(the longer you cook it, the more chlorophyl and other nasties that get killed off)
6. Once you have let it boil for this long, strain out all the trimmings, get all the juices outta them into the pot..and boil longer
7. When the pot gets very shallow, put on simmer and stir until the oil is the same consistency as thick caramel.
8. While on the simmer, put two teaspoons of sugar to neutralise the acids (So it can be smokable, otherwise it only absorbs in mouth and throat, not in lungs)
and that's it....it'll take about 9-12 hours to make..but the more boiling, the more impurities you kill off..
The end product should be a dark oil that when spread evenly, should have the same colour as honey...oil with green in it means it still has too much chlorophyl, so it is shit in other words...
And that's it.....This is the best way to make hash oil in my books, and I find the quality rivals most extractor made oils.
There is also a way to turn the honey hash oil into pure cannabis essence...but I will not go into it as it needs a lot of prep and the product is too potent for most ppl.