There are two ways to use strips:

1a) Dip the strip and look at the FC/Free Chlorine side. If it's white, I
have a problem. If it's deep purple, I'm probablly OK. Anything in
between I test with something ELSE that's more accurate.
b) Ignore ALL the other tests on the strip--they are totally worthless
because they are extremely inaccurate.

2) Don't use test strips.