Once you've got the basic movement and grip more or less right the thing is to play along with music, not worrying about whether you get it right all the time while your hand is getting educated.

There are a whole range of variations in exactly how you hold them, and you can vary the sound by sliding the anchor bone forward or back, or adjust them so you beat at one end or two ends. And you can even hold them in different hands, when your wrist is tired, and play like a bodhran.

Now spoons ans castanets are a different matter entirely. I've never managed to work them.