If you have the humidor 'seasoned,' there is no special prep work needed for your humidifier. Add the 50/50 solution into the humidifier's vents, wait a few minutes for it to absorb, (you want the sponge relatively damp NOT soaked) and wipe off the excess.

In the future, when your humidity starts to go down pass the threshold you desire, add more 50/50 solution and you should be set.

Welcome to the board btw...