What is the way to add already highlighted objects to a selection set?

[aawilds]

What is the way to add already highlighted objects to a selection set? I feel like I have seen the answer before but I cant remember what I searched to find it. Like how you can select object before you use the move command and autocad will move the objects that were already selected. I am looking to use the TSPACEINVADERS command and have the selected text then have a red circle put around them. Thank you for any help in advance.

[ronjonp]

Make sure pickfirst is set to 1 then calling (ssget) will create a selection set of the highlighted objects.

[aawilds]

Thank you. I knew I had seen it before just could not remember.