For a 45/180 procedure turn, start the timing before the turn, and time for one minute, wind corrected, before turning inbound.
If you forget to start the stopwatch, an alternative is to start the stopwatch after the turn, then to go for 45 seconds. (That's based on the fact it takes 15 seconds to do a rate 1 turn through 45 degrees.)
If you're talking about an 80/260 procedure turn, it's been a long time since I've done one, but I don't think there's any timing involved. I'd have to check that to be 100% certain, but I'm sure someone else will either confirm that or put me right.
FFF
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