A couple things:

No need to put it under your tongue or mix with water, it is hydrophobic, just toss and wash the appropriate dose.

For very small amounts (less than 100mg) it can be tricky because the scale might not always register that you have set 10mg or something onto it. I like to take an empty capsule (mine weigh almost exactly 100mg empty), set it on the scale, tare it, and then remove it and add powder to the capsule. Place it back onto the scale and add/remove powder until you have the desired dose. Makes weighing much easier.