You can create color tags and use them for Sales Orders. Color tags shows up in the order listing page. You can use it to note important orders or use it to indicate status.
First set up your tags in Setup, Quick Tags. Each tag can have a short description and a color. Choose from the color palette or choose a color name.
Once the tags are setup, you can click on the View menu on the order listing page and choose assign tags. Assign one or more tags to the order. There is a column called Tags that will show the tags you have assigned to the orders.