The Store Connector switch lives in your theme and lets Navi+ show on your store. Until it's on, even a finished menu won't show.
1Open the theme editor
Shopify admin: Online Store > Themes, click Customize next to the theme you want to use.
Tip: if your store has active shoppers, turn it on in a copy of the theme first (Themes > … > Duplicate).
2Turn on Store Connector and click Save
The left bar opens App embeds. Turn on Store Connector, then click Save.
3Check in Navi+
Back in Navi+: Tools > Embed Navi+, your theme shows Navi+ on.
After turning it on, the menu still won't show right away: you also need to click Turn on in the Publish window of each menu.
Changed or duplicated the theme? Turn it on again
The switch belongs to each theme. A new theme or a copy that isn't turned on won't show the menu there, so do the three steps above again for that theme.
Menu disappeared after changing themeOther platforms
The steps above are for Shopify — the default way.
On Wix this step doesn’t exist: installing from the Wix App Market already attaches Navi+ to your website.
WordPress and other websites don’t have this step either. WordPress: turn on the Embed Navi+ Menu Builder into website switch in the plugin. Other websites: paste the code into the head tag. See Wix, WordPress, other websites.