I've tried the antiperspirant idea in the past without any success. It eventually broke down and reacted with the glue and became very visible.
I've also used liquid bandages but eventually the sweat/oil built up underneath and the attachment was weaker and if anything lasted a shorter amount of time.
I'm currently trying ProTouch No Sweat.
The jury is still out on that, as its not really been put to the test.
We're having a rubbish Summer in the UK and apart from the odd humid day the temperature isn't causing as much sweating as usual.