It is important to keep the skins dry both on the glue side, and the plush side. Dry skins will give traction. In the spring time often times skins will gather moisture in wet snow on an ascent. As you get in to shady area and /or increase in altitude the moisture will freeze and accumulate snow at a rapid pace. Before you know it you will be bogged down carrying snow on the base. Even worse is icing where the skin will fail to gain purchase. This can be a big problem on a steep incline or traverse.
In order to keep moisture from accumulating on the skin it is important to wax the skin with Glop Stopper Skin Wax, pretty much a must in spring conditions or temperature inversions. I have also used a scrap piece of regular all temperature wax and it also worked just fine. I prefer to use Glop Stopper since it is a little more friendly should it come in contact with the skin glue.
To apply wax on your skins, mount the skins to your board or skis. Make a single pass from tip to tail (with the plush, NOT against it). If you build up to much wax by going against the plush you risk losing purchase when climbing. Touring with snow-caked skins will only happen once – after which you will always carry skin wax as an essential part of your backcountry gear.