Injecting - Keeping out the cut

[steady_mark87]

Swim has seen heroin IV'd bunch of times before but never cocaine.... searched the IV sticky thread but no-go. When SWIm saw people shoot H they would mix it up in the spoon till it dissolved then throw in cotton from a cig filter, he said it was to keep the cut out and reduce the amount of air that gets in the spike.... is this the same for yayo too? or can u just stick the needle in the water and go at it? i hear a lil air aint too bad