Here's my favourite tip with the brushes like 217 & 224 that can feel a little big around the crease... after you've cleaned them, gentley twist the fibers ( I do it clockwise, because I'm right handed, I suppose ) so the end forms kind of a pointy tip. let it dry like this.. after a few times you'll notice the brush has reshaped and will fit a lot better into your crease... and after you reshape it, you can also use it like a wand, too, and blend by using a sweeping motion as well as the circular motion most people are comfortable with.
hope this helps.