There are a few ways to secure the lashes which you can also see on the video tutorial. When I trained I was taught to use just lash pads but I know that other techs are taught to use micropore tape. I think both have their benefits and disadvantages and I now use a combination of both to make sure that I don't end up with bottom lashes stuck to the top ones at the end of the treatment. I have found that micropore tape on its own, although great for securing the lashes, can be really quite uncomfortable when you remove it. Even when you try to remove most of the tackiness first and although the gel pads are more comfortable, they aren't very reliable at keeping lashes stuck down. So, as a happy medium I cut thin strips of micropore tape, just enough to keep the lash down but not enough that it attaches to the delicate skin under the eye. I then apply my gel pad on top.
After you have padded up and you are happy that all the bottom lashes are secure, use your dental mirror to just check that there are no gaps in the lashline. Fumes from your adhesive will be drawn to the moisture in the eye and if any of the eyeball is exposed while you lash there is a good chance that your clients will experience irritation. This can cause your client's eyes to feel sore and appear red and bloodshot so try and keep those eyelids fully closed. In some cases, usually if clients have had surgery on their eyes,they may not be able to fully close them. In this instance you can place a damp cotton pad on the cheek to draw the fumes away from the eye to prevent a reaction.
There are various other ways to pad up as well. Microfoam tape is an excellent alternative albeit quite expensive. It provides a good amount of cushioning and is also very gentle on the skin. An added bonus is that you don't have the worry of your client being allergic to any of the ingredients. To use microfoam tape you can just cut it into strips and cut into at intervals on one side so you can manipulate it to fit around the eye.