One important SEO step that I've always procrastinated on has been keyword research.
This step is where you comb through the data in order to find out what searches people are actually using (keywords). This is important because it doesn't matter if you pick a cool sounding phrase for your store's SEO, it matters if people are actually searching for it.
For example, if you sell automobiles you wouldn't target the keyword "buy automobile", you'd target "buy car".
Keyword research will tell you that nearly 0 people search for "buy automobile" each month but 60,500 search for "buy car".
If you targeted "buy automobile" you'd waste your resources.
Even if numbers aren't your thing, keyword research is still important. Just discovering similar phrases that people search for can help you find some areas to target.
There are a ton of keyword research guides out there with all sorts of advice. I haven't found one I like and would recommend so I encourage you to read a few.
Keyword research isn't Shopify specific either so you can follow any guide and use non-Shopify tools to do it.
The tool I use is called SEMRush, though Ahrefs and Moz are popular alternatives. Google even has their own as part of their advertising system but its data is vaguer and not as useful (but it's free so that's good).
Today would be a good day to Install JSON-LD for SEO if you haven't yet.
You still have a couple of months before the holiday season. Just enough time to start getting Rich Snippets and beating your competition in the search results.