I have all the things I need to start building it, but I can't find a diagram that suits my needs, if someone could recommend a good one for me I would be very grateful!

Basically I need an A/B Y looper that can be bypassed.. For example I press the A switch and I get access to one loop, then If I press the B switch I get access to other loop, and when I press the Y switch it enables those two, but you can either bypass loop A or loop B by pressing the A or B switches...
It sounds a bit confusing but If someone could help it would be great