Can someone send me over a guideline?
Thanks!
Watch this space - in a few days I'll be posting a step-by-step guide to FB ads for eCommerce, which will contain a lot of transferrable info.
In the meantime: if you have any way to generate a lookalike audience, start there. If not, mine as deep a set of interests relevant to your offer as you can, split-test between those in targeting, put ONE AD in EACH ADSET, and otherwise operate as you would normally for any traffic source - see the Getting Started Guide.