1) encourage him to foreplay with you more, women need more time than men to climax so you should get 'started' earlier.
2) try taking control, use his body the way you like it until you are ready, when you are about to climax be vocal to let him know (passionately if possible), this will excite him and build him up so he would be ready at the same time. (a minute should be enough, most men are easy to trigger if you do it right)
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