Promoting is such a difficult thing, especially online! You need to have your fingers in all the pies, but remember to not spread yourself too thin. I ended up joining far too many social networking sights and missing my audience completely because I was too tired and busy to keep them updated and interested.
Forums like these which are linked to the shop you sell from are a very good place to start. Twitter is also very useful, it can get overwhelming but stick with it! Charities get a lot of exposure and help on twitter. Pintrest is also becoming the next best place to showcase your products as pins can go viral quickly.
I found that the most effective way to boost sales is to get out there to as many events as you can (preferably free) maybe even try and host something yourself? An afternoon coffee event somewhere with friends and friends of friends? Even if its a small turn out, one nice face to face event can work wonders for sales!
Your jewellery is beautiful and I shall be sharing your shop on facebook and twitter!
I hope it helps, best of luck!