so im seeing alot of suggestions but nothing too scientifically tested (no offense to anyone). I too have struggled with making edibles and have found the following rules help out (especially w/ my high tolerance):
#1: TRIM is awesome. doesn't have to be bud. however, the better ur trim/bud, the better the "high". either way you'll be stoned...like stoned. hard. haha.
#2: DECARBING. this could mean a whole bunch of crap, but basically after many tests, i've concluded it means "heat the friggin weed in an oven at 240F for 1 hr". i like to cover/wrap my buds in parchment before putting in the oven to prevent any possible scorching.
#3: SOUSVIDE/MAGICAL BUTTER MACHINE. you need either one of these devices to produce quality results. however, if not, just keep this in mind. weed needs about 3-4 hrs to infuse into butter properly and about 1-2 hrs for oil. you can use the same temperature for both but the weed has to infuse at a consistent temp of 160F for the entire remaining time. a consistent temp of 160F will gently infuse most of the thc from your plant matter w/o killing much of it. Therefore ending up with close to 90% of your thc still in tact. (Google: sous vide. you can find many lower priced sous vide machines for cheaper these days. sous vide is good for many things actually, but in this case it makes this process 100% painless. almost like set it and forget it.
do not infuse trim/bud into oil/butter at temps higher than 250F. above 250F kills thc and all the goodies. keep it consistently at 230-240F and you'll be happy to know most of your thc is still in your product.
once you've made the butter and bake other things, the higher baking temps cannot be avoided, and may in fact help bring out a better high in your end product by doing so. (think of how fire flames hitting buds cause amazing highs, lol, idk makes sense to me.)
at any rate, if you're confused at all just remember:
#1) 1 HOUR AT 240F (CAN BE DONE IN OVEN OR IN SOUS VIDE WATER BATH, EITHER WAY IT HAS TO BE 240) TO ACTIVATE THE THC IN THE BUD SO YOU CAN GET HIGH
AND THEN
#2) 1-4 HOURS AT 160F TO TRANSFER THE ACTIVATED THC INTO BUTTER OR OIL. 1-2 HOURS FOR OIL. 3-4 HOURS FOR BUTTER.
GOOD LUCK! (oh yea and grind up your weed real good AFTER the decarb, not before. the butter/oil cannot reach parts of the plant if they're not exposed.)
awesome resource for how to make weed work in food:
http://www.thestonerscookbook.com/how_to_decarboxylate_weed.php &
http://www.marijuanagrowershq.com/decarboxylating-cannabis-turning-thca-into-thc/ (both have well written instruction, charts, graphs, etc. very easy to understand, you'll be makin edibles in no time.)