Get a lot of female plants that have grown all the way and may even contain seeds. Make sure they are absolutely dry by hanging them in a shed for some weeks. Now take off all the leaves that are bigger than 1/2 inch. You end up with just a stem with some buds sitting on it.
Now strip off the buds into a container. (BTW, Hash (moroccan style) consists exclusively of the pressed grains of resin that are sitting on top of tiny resin glands that are most abundant on the leaves surrounding the seeds, or flowers. when the plant is dry this resin hardens to form a very small particle, called “pollen” which is not actual pollen however.)
So now you’ve got all the clean buds start crushing them over a kitchen sieve (mesh size about 0.5 mm). The seeds and stems will stay on top of the sieve. “Grind” the leaves gently through the sieve. You end up with a sort of powdered leaves. Be sure that the thin skins that surround the seeds are included in this result, because they contain most of the resin glands.
You may repeat this process using a sieve with an even smaller mesh size. (0.25 mm). Then take a cloth with the appropriate “mesh size” and rub the powder you have already got over this cloth. In the ideal case, only the finest particles pass through the cloth and will ill consist only of tiny grains of resin. Now take this powder and wrap it into a sheet of kitchen plastic foil. Now press this “package” between a few logs of wood. The result is a sheet of hashisch. If the sheet falls apart again you’ve got too much leafy stuff in between the resin. Try a cloth with a smaller mesh size the next time. This procedure is only advised when you have so much weed to spare that you don’t possibly smoke it all in a year.