I've recently started building my Copic collection and, for those not familiar, these are alcohol-based markers for illustration and design. Copics, in particular, are very highly regarded and generally the gold standard for alcohol markers. What I like about them is the rich colours, the blending capabilities, and the logic colour structure that helps guide your selections when colouring.
In any case, Jazza uses Copics extensively in his videos and so has built up quite a repertoire of knowledge on the topic.
It should be noted that some of these tips will apply to other alcohol markers, so if you are using Touch, for example, there's still value in this information.