How do you tie dye drop cloth?

you will need rubber bands or string for the tie part,- gather clumps of the fabric add rubber bands. the rubber bands/string should be put on tightly. then make your dye bath and the dye fixative. where the bands are and the string is should keep the original colors of the fabric. every thing else the color of dye you chose to use.

You should wash the drop cloth first to remove sizing and water repellant for die to take better.

Here is Rite Dye techniques..... https://www.ritdye.com/techniques/tie-dye/

You could also buy the powered dye and ice dye it..... https://www.ritdye.com/techniques/ice-dye/

Here is how to rubber band a piece.... https://www.youtube.com/watch?v=ygQwq7Dsnu4

ice dye techique... https://www.youtube.com/watch?v=Zbhy3BtYtcQ

I'd wash it first and then you tie-dye like any other fabric.

Here's a tutorial: https://www.tiedyeyoursummer.com/how-to-tie-dye

Here is a fun idea from Hometalk https://www.hometalk.com/diy/craft/holiday-crafts/faux-batik-and-tie-dye-patriotic-table-cloth-1747414