When you bring any woody-stemmed flowers or branches home, there are two ways to prepare them:
1. Make a fresh angled cut with a clipper then take a hammer and smash the stem so that it splays out. This will allow a lot more water to get into the stem.
2. The other way is to use clippers for a fresh angled cut, and then cut again with the clippers -- this time straight up the middle of the stem. This, too, is to allow water to draw up the stem.
The two techniques outlined in the video are known as "crushing stems with hammer" and "splitting stems open".
If you would like to know more about these techniques and other similar techniques, visit this page about how to care for cut flowers.