Pumps and tucked in shirts...

I have a question for veteran pump users: How do you handle your pump when you need to wear your shirt tucked in? I just got my first pump set up the other day and I typically wear a dress shirt with an undershirt to work (tucked in), but the best setup I could think up is to hold the pump with a SPIbelt I got under both layers. However, this means that in order to access the pump, I have to go to the bathroom and untuck everything. Is there a better way to handle this?