Remove existing finish - only where you want to refinish, in this case the top. Paint the finish remover on, wait the specified time, and strip it off with a putty knife, according to the instructions. Do this outside for ventilation and because it's a messy job (I did it in our garage). I used Citristrip and it did fine for the top.
Wash the top with mineral spirits and steel wool and then sand it with an 80-120 grit sandpaper.
Base and table top skirt - if you're painting the legs and skirt, just sand them as well as you can with the same sandpaper. Some legs are full of crevices and bumps and hard to reach, so do the best you can. If you want to refinish them, you'll have to use the finish remover on them, too, and use a wire brush to get into the crevices.
Step 2: Prime the Base
Cover the top with plastic taped underneath the table top to protect it from the paint. Also cover any metal base feet with masking tape.
Spray paint the table skirt and base with a flat finish primer (one can covered this base). Spray gives a smoother finish and is a lot easier, though it costs more. That said, you can brush paint on as well.
Step 3: Paint the Base
Spray the table base with two to three light coats. Move quickly with light coats to avoid drips. To make it easy on your hands, use a spray paint can gun - I love it!
It took one full can to do one coat and I did two coats. You can also brush two coats of paint on. Sand the base after drying to distress, if desired.
Step 4: Sand the Top Again
Sand - after letting the base cure a few days, remove the plastic covering from the top and give it another light sanding with 180 grit sandpaper.
Wipe it down thoroughly with a tack cloth (this really does collect the dust better than a regular rag).
Step 5: Use A Wood Conditioner
Brush a water based pre-stain over all the areas to be finished, according to the package instructions. This will help the stain go on more evenly.
Let the pre-stain dry at least 30 minutes before staining, but not more than 2 hours.
Step 6: Stain The Top
Apply your chosen stain to the top and edges according to the directions. I used Minwax water-based stain in 'American Walnut.' You can use gloves and a rag to apply or use a disposable foam brush, which is what I used.
Use as many coats as needed to get the look you like. I applied two coats (over a couple of days) on the leaf and three on the table to get the look I wanted. This really helped to lessen the difference between the darker leaf color and the main table top.
Step 7: Protect With Polyurethane
Apply three to five coats of water-based polyurethane after letting the stain dry completely. DO NOT sand before applying the poly, just wipe with a tack cloth to remove any dust. I applied five coats because I wanted the top to be very durable, keeping the foam brush in a baggie between coats.
Let the poly dry thoroughly between each coat. You can sand with a very light sanding paper (280-320) or not - it's up to you and how the top feels. It's usually recommended, but I didn't as it was smooth in between the coats (maybe because I was using water-based products?).
Let the top fully cure according to directions before using, usually 5 days to a week.
Notes
TIP: I learned three things applying the polyurethane to the table:
Always use a wide foam applicator instead of a brush. I had brush strokes from a natural bristle brush in the middle of the table in the first coat that I spent the next four coats trying to minimize.
Do long strokes with the grain from one side of the table to the other, not from one side to the middle or you will have a line.
Start in the middle of the table and work towards you (yes, I have a shirt with poly on the bottom of it now...).