I mix ground herbs with a bit of makko powder and just enough water to make a dough, then shape cones and let them dry a couple days. It’s pretty forgiving once you get the feel for it. When I want to compare scents or see how something should burn, I use a few sticks I got from
https://nothingbutscents.com/collections/incense , which helped me tune my own blends without wasting materials.