This article is related to PromoteMyPlace Version 2 only. Not sure which version of the application you're using? See Which version of PromoteMyPlace am I using?
You can watch the following video or read the article below it.
From the ‘Website’ dashboard, choose ‘Menus - Main Menu’
Select the menu item that you want to move by holding down the left mouse anywhere in the box
Drag the menu item to where you what it to be positioned in the list and drop it by releasing the mouse button
Save your changes
Once you’re ready to put your changes on the live site you will need to publish the website changes