#1 - Don't welcome me to your shop.
Really, don't, at least not right away. Not because you don't want me and other buyers to show up, and to feel welcomed, but because starting with that friendly "Welcome to my shop" is such a waste of the key first characters in your valuable Shop Announcement space!
"The first 160 characters of your Shop Announcement are used to create the meta description for your shop page. The meta description is the text shown under your page title on a search engine results page.
TIPS: Describe your shop and the kinds of items you sell. Use welcoming language that will entice someone to explore your shop further. Use keywords that you think shoppers will search to find your items."And when was the last time someone searched for "Welcome to my shop!"?
Read the article, here. It's a much-shortened version of the big 25-page SEO Guide. You'll also learn about how to make the shop title, item titles, shop sections and item descriptions work harder for you.
Images from SurrenderDorothy and justmars, thanks!