either of the two wires tø the coil will stop the primary circuit.
Or you can ground out the secondary wire from the coil to the distributor...I prefer the latter. I would also disconnect the terminals to the fuel injectors....you don't want fuel going to the cylinders while you're cranking them for compression.

don't forget to squirt oil in the cylinders after you've done your first compression check (with the engine warm....BTW, even though the plugs are supposed to be removed when the engine is cold, if you've coated the plugs with antiseize you can usually remove them after a half hour or so without an problem. If you haven't pulled the plugs in 30K you need to replace them anyway....) if the compression rises more than 10-20 pts, you've got excessive ring wear or perhaps sticking/stuck rings in my opinion although the car may run ok.