I'm a sucker for a cat eye, but who isn't? For a while now I had just been using a kohl pencil on my lid, but thought that the colour wasn't strong enough. I then came across Soap & Glory's Supercat which just so happens to be blacker than black and super intense. The eyeliner is almost like a felt tip and it's very easy to use - the dense tip gives me enough control to get right up against my lashline without causing havoc.
I'd definitely recommend Supercat if you're an eyeliner beginner or just not a confident 'flicker'. Other eyeliners I've experimented with tend to have longer applicators that aren't stiff enough to guarantee perfect precision each time. I've also had experience with liners flaking but this stuff will last you all day and isn't the slightest bit drying.
If you find it difficult to apply liner it can be easier to go step-by-step, repeating each part alternatively on each eye so as to keep things symmetrical. You can also practice your liner with a pencil first getting your basic shape, and then apply a liquid over the top if you're nervous. Also, if you're not sure of what shape to follow, simply imagine the curve of your lower lashline continuing on and the same angle - easy! Oh, did I forget to mention that it's only £6. I know, amazing right?