What I do is hold the female outside the male's cage and watch the reactions. This keeps hem both safe while you determine if they are "in the mood". If the female does not darkened colors (taken non-receptive coloration), hiss, sway back and forth, gape, etc but remains calm body not inflated and may move slowly away from the male and the male does not show aggressive posture or coloration you can put the female into the male's cage. I continue to watch them for a few minutes but if all is going well you can leave them alone until the female starts showing her gravid non-receptive colors or acts aggressive towards the male.