how would i assemble something like this?

[Steve Flavin001]

jig - ideal for this. I made the Wood magazine three stacking tables identical in concept, using it. Can also use screw in top covered by wood plug re lifting concerns expressed.

[Scott Rollins]

I like Rons 2nd idea with a twist. Mortise and tenon the aprons to the legs as with any table. Then veneer a mitered frame to the top to create the rabbet for the glass top and cover the end grain. Flush trim with a router on the outside and done.