Hi,
Usually, the USB Mini/Micro cable should do the trick for you.
If you want to have an OTG port, then you design in an AB-plug, where both connectors fit.
Generally speaking, the A connectors (which sets host mode of OTG port) are bigger than B, and hence the former only fit in AB-plugs, whereas the latter fit in both.
An A cable connects the ID pin to GND, and a B does not.
If you want to connect a thumb drive, then get an adapter from Mini/Micro-A to A-plug.
Best regards,
Harald Krapfenbauer
Bluetechnix