Calling all my fashionista friends....

Yo mamma needs some help.

I bought these shoes today to wear to my Uncle's wedding on Saturday. Normally, because I have frigged up feet, I wear nylons with dress shoes. If I don't, I get blisters from hell. But, the forecast for Saturday is for temps in the upper 80's, low 90's so I just can't see myself wearing another unnecessary layer in that kind of heat.

[As an aside, my sisters and I are also singing two songs during the ceremony so my panic heat will also be in full throttle as well]

My question for those of you that love me so is this: Is there anything I can do to prevent the strap closest to my toes from bringing on a blister? Powder? Anything other than wearing nylons? I fear blisters. I did buy them a half size bigger than I usually wear to compensate for the "being on my feet, hell, my toes for hours on end in extreme heat" swelling I can already foresee happening. But, is there anything else to curb the friction?

I hate feet.