Masturbation should not be accomplished as a rule like morning and evening tea, or lunch and dinner. It should be taken just an alternative of actual sex under a situation when it is not possible to have sex. This means :
1. For married persons, if wife has gone some where for a few days and you are habitually needing a sex.
2. For widowers or divorced persons who have no alternative except to use hands for satisfying the biological requirement whenever it becomes intense.
3. For unmarried males, if they feel extremely aroused to see big boobed girls or ladies, or even small-boobed semi-exposed girls or ladies, or their undergarments.
But in every case, one has to be judicious enough to use your God-gifted tool with a frequency such as to enjoy equally well every time. And this can be possible only if you give a proper interval which may vary from 1 hour to 1 week depending upon once sensitivity and control to ones horny feelings. The best advice would be that whenever you feel your masturbation to be more labour-intensive (with the release of lesser amount and thinner density of semen) as compared to your just previous course of masturbation, you must understand that you have gone for it more quickly. Accordingly, you can yourself decide about the minimum gap you should observe between two courses of masturbation, so that you can remain healthy and equally justify during next course, as also during actual sex with a female partner without any apparent loss of energy & potency.