As for the rest of the closet, I removed the old wire shelf and installed the cedar closet liner planks with brad nails nailing into the studs), and liquid nails. (shadesofblueinteriors.com)
Our nail gun uses brad nails that produce tiny little holes that are easily covered. (jennakateathome.com)
We used 4 × 8 wood floor underlayment from Home Depot, cut into 6» strips and installed using liquid nails and a small brad nail gun, using nickels as spacers. (homebunch.com)