boolean selector for relay control

[airnate]

All Booleans in LabVIEW are green in color and can only be True or False. Alternatively, you can use an enum (short for "enumerated type"), which is actually an unsigned 16-bit integer. You'll find it in the Numerics palette. Once you drop an enum into the diagram or front panel, right click it and select Edit Items (there are quicker ways to edit the names, but not as self-explanatory).

You can then add as many items as you like. In your case you would add a "Forward" and an "Off" item.