Two rolls of the best-quality cloth tape we've used. It comes from Japan, is sold in pairs, and it's long enough (per roll) to do half of a wide drop bar.

Most of the time on the bike we assemble, we shellac it with Bullseye brand amber shellac. The amber warms up the colors a lot, turning cheap clown red into a rich, uppercrust oxblood. Look at the detail shots to see the effect of clear and amber shellacing.  Here's a video on how to shellac cork grips and cotton tape.

And here's a link  that shows how to finish off your wrap with twine.



Cloth bar tape shootout:

Width:
Tressostar: 19.5mm
Viva: 19.5mm
Newbaum's: 19.05mm (3/4-in.)

Length:
Tressostar: 8.5 feet
Vivian: 8.25 feet
Newbaum's: 10 feet

At least two rolls of Tresso and Viva tape are needed for bars up to 44cm wide; three rolls if your bars are 46cm or wider.

Only two rolls of Newbaum's are needed for even the widest bars since the tape is so long.