In general you’ll want to hold spinner between you thumb and index/and or middle fingers. Easiest and faster way to spin is by holding it with one hand and flicking it with the other.
You can also hold and spin fidget with same hand, by using your ring finger for example to flick it. Be careful tho, as edges are straight and might be a little sharp.
Another fun way to spin fidget is by placing it on the table horizontally and spinning it there.
In our testing we discovered that fidget spins the longest when it’s held vertically with nothing on either side of the spinner. Spin time reached 2 minutes and longer when our premium ceramic hybrid bearing was used. In fact we even tested various very expensive full ceramic bearings and spin times were pretty much the same as. Read more in the bearings section.