This is easy as it already has aerial roots. Cut off the long stem just below and pot it up. Don't water it much, especially after the surgery. The only thing they don't like is cold and wet. Good Luck.

That propagule should be able to be cut into pieces so it yields 1 single stem plant and at least 2 multi-stemmed plants.

Al

To build on the suggestions above, I would put the tip with about 2-3" of stem attached into a pot in an upright position. Then I would put the naked length of removed stem in a pot sideways, might need to cut it again so it fits unless you happen to have a very wide pot. It is likely to produce multiple root systems and stems that way. Some pics for reference:

https://forums.botanicalgarden.ubc.ca/threads/philodendron-bipinnatifidum.93039/

This trunk may have produced more stems if it was in contact with the soil and thus able to take root at multiple nodes.

https://austinbotany.wordpress.com/2014/03/27/philodendron-bipinnatifidum-king-philodendron-tree-philodendron-split-leaf-philodendron-selloum-old-name-philodendron-selloum/