But why not just take it sublingually and avoid the hassle altogether? A lot more gets absorbed that way compared to dosing it orally. Just put a tiny bit under your tongue once you get a feel for how many mg of powder it takes to fill up whatever you use to scoop it with, and hold it there until it dissolves (or drink some water to get the remaining amount down).

You can take massive doses of melatonin without any potential health risks so you don't have to worry about being too precise in amounts, though higher amounts take more getting used to.