Every 3 hours if you really wanted to be high speed about it.
Otherwise, take them at equally spaced intervals throughout the day, there is a common misconception about orals that taking them in the morning somehow "fools" your body since this is your body's normal time for Testosterone output. This is not the case, any exogenously administered androgens will be detected and turn off your GnRH and FSH likity split.
Also, T, to my knowledge is not controlled by circadian rhythyms, which would have to be the case per this theory.
Cortisol, GH, etc are. Not T.
NFG
Oh yeah ... if you want to be a hero with it, take each dose with 1 c grapefruit juice, something in that shuts down CYP 450 E in the mito of hepatocytes and prolongs the halflife (hence the serum concentration) of many classes of oral drugs.