Here goes:
The seat height should be 20" to 21" so will need the correct amount of padding to get their.
What you will need:
Burlap or FLW cloth or similar stapled over springs,
Edge-roll (search terms "edge roll for upholstery"
Seat decking: a dense fiber pad to isolate between springs and foam,
Polyurethane foam; 1.8 density 32: to 45 ULD, depends on thickness of foam to bring seat height up to correct height,
Cotton or polyester padding over foam; this makes pulling fabric down and around the seat.
Best to upholster a muslin cover first, before attaching the fabric.
Check in local yellow pages for upholstery supplies or search online.

Thank you so much for taking the time to respond!
I have a lot of things to learn to get this one done.
Any other advice or ideas welcome...
Thx!

Check out this link below. It has pictures that may help you to envision rmanbike's process. You won't need to pay attention to her spring tying technique. Just scroll down to where she attaches the burlap, edge roll, etc.

Also, a helpful book I've used is Singer Upholstery Basics. I bought it at JoAnn's Fabrics, but it's likely available online.

Here is a link that might be useful: Betsy Speert Chair Project