For non yacht persons, line handling can be a bit challenging. But most cruisers would rather have someone on board with the right attitude that can be shown what to do, than some of the “professional” line handlers who don't seem to care or don't pay attention (a generalisation).
How to line handle
You should practice doing a clove hitch (or ask the skipper to show you) as that is a good knot to tie the throw-line to the mooring line. You are under a bit of pressure once the throw-line is hurled at you to get the mooring line all set up and ready to feed out.
If you cannot do a bow line, then ask someone else to create the 3ft loop in your mooring line (you will only need to create it once so don't worry if you cannot do one)
The main rule is do not drop / let go of the mooring line!
Its the skippers responsibility for the boat and its crew (i.e. you). Don't get upset if the skipper checks knots or wants things done in a certain way that might not be your preferred method. After all, it is his house that you a guest in and therefore his rules.
For the skipper going through the canal, his stress levels may be rather high. He has to try to manoeuvre his very expensive home in a tight space under conditions he is probably not used to...
Sometimes voices can be raised a few decibels above the ordinary level and sometimes certain expletives are used to describe tense situations. Do not take any of it personally. Remember to try put yourself in their shoes. But once through and stress levels subside, you can be certain of having a story to tell and maybe a lesson learnt.
What to expect
You will be sitting around doing nothing for most of the time. But when you are required to do some “work” remember to manage the mooring lines as you have been instructed as your first priority. There will be plenty of time later to take photos or admire passing ships etc.