Place the sticker-labels provided with your N-Dexer purchase on top of the printed template, taping edges of label to printed template. It only requires a small amount of tape along the edges to hold in place. Be sure to not cover any of the labels or the printer will print onto the tape, and you'll have to redo this process to rectify.
Load paper into printer, making sure to feed into the printer correctly such that the printer will re-print in the same place.
Return to blank template on your computer. Fill in card names, color, rarity, set or any other organizational markers you want, in each blank label cell.
Print out sheet, pull off labels and attach to N-Dexers tabs.