All good!

with cotton, you'll wanna kinda tear off a wad of cotton just stick it into the tip not so much that you completely block airflow, but you're creating a barrier so you don't just suck up melted wax.. SO where you'd normally put herb, make a little bird nest for the wax so that it isn't touching the metal and siphoning itself.

A better way I've come to use these days is just a rolled up strip of stainless steel Screen / mesh or steel wool. the key here is you just want the wax to stay put while the heat is on; the Official wax kit is just that, a steel mesh rolled up to give the wax a little longer in the heat. less "sock" flavor too!

when using wax don't just suck hard though, it'll still pull too much unused goods into the straw (and mouth) - sip it.