I've found that not all of the "clinical strength" antiperspirants work the same. I've found Secret to be the best with Degree an acceptable alternative. The directions on all of them say to apply before going to bed. I usually take a shower before bed, then immediately apply the antiperspirant. I don't get dressed right away, I let it dry a bit first. If I know it's going to be a particularly hot day, the next morning I will apply again.
Towards the end of each shower I gradually start to turn the water to cold to bring my body temperature down a bit. It's nearly cold by the time I step out. I dry off right away and then use Shower to Shower body powder on those spots where I tend to sweat a lot. Baby powder doesn't work nearly as well as the Shower to Shower.
If you have trouble with sweating under your bra, you might find placing a triangularly folded washcloth placed between the bra band and your skin keeps away a lot of the excess moisture.
Every chance I get throughout the day I use a very cold, wet facecloth and press it against my face and neck to bring my body temperature down.
Sorry this got so long, I hope it helps!
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