How am I supposed to wear a running vest?

[giraffescantdancethetango]

I am running 10k for Tommys. I wasnt sure over vest size, but ordered a large one. Surely I am meant to wear it over something otherwise it would be rather revealing, but what am I meant to wear it with? Or should I have a smaller size thats less gaping at the sides?

I wear my charity vest over a close fitting, wicking T-shirt as otherwise the seams and underarms would rub me raw. I don't know anyone who is comfortable in just the vests.

Good luck with the run!

This type of thing

Thanks