This is so easy to apply, simply dabbing onto the teeth. I do have my own custom trays so I'm not sure if this makes the process any easier than a generic tray, but I have had fantastic results in only a couple of weeks. I put the tray in before I shower and just brush my teeth when I'm ready to go out, usually leaving on for either 10-20 mins at a time, once or twice a day. Now they are lovely and white I can leave them to re-do maybe a few months down the track. I have tonnes left in the tube, a little goes a long way. This supplier was also SUPER SPEEDY at delivery. I highly recommend this product, it does what it says!