What time of day is best to take a Clear Blue Digital ovulation test?

I bought clear blue digital ovulation tests, and I've can't find an answer to what time of day it's best to take the tests; some articles say between 10am and 5 pm is best, that first morning urine is not as accurate. Then other articles that I've read say morning IS best. I'm confused as to which I should do, has anyone used these tests? If so, what time of day did you take the tests?