Commissions: How Hard?

I've been thinking about this for a while, doing commissions, and I'm really thinking that it's a nice idea. I'm pretty good when it comes to drawing pencil portraits of people and have wanted to sell my art for a long time. But how hard actually is it to begin doing commissions? From actually gaining enough traction in the art world for people to be interested in my work, to organising to do it, to even just all the time and money I'll need to spend to actually do this. Even if I do end up doing this, I'll also need help in what sorts of websites and methods to use to make it work.
To anyone on here who has done or is doing commissions of their art, please help!
@dedofspace
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