How do I insulate my 1960 home in the most economical and quickest w ?

You can DIY (2 person job) blown in attic insulation. Most big box stores will let you rent it for free if you buy insulation from them. You pay a deposit but they refund it.

A bigger project would be the windows. Add storm windows and caulk around windows. You can replace with double insulated windows but that's not quick or economical.

Check for drafts around doors. Make sure they are sealed. You might want to add a "draft dodger" at the bottom of the door. We have one on the bedroom to keep it cozier at night.

Add rugs to wood or tile floors.

Also lined draperies really help around windows and sliding doors.

Use the 3M window coverings. They are relatively easy to apply and shrink down with a hair dryer and really do keep the breezes from around the windows. Check to see if you need to recaulk around the window sills and the outside of the window frames. You can even use the 3M system on sliding glass doors and French doors. I use to do my mom's every year until she moved out of her apartment. Like was mentioned before, check for drafts around all the doors to make sure they seal tight. If you have drafts from outlets, they have little foam inserts you can put behind the outlet cover to help with that.

whats a 3m?

With older windows lined drapes help cut down on heat loss.