Once your cucurbits (pumpkins/squash/courgettes) get growing, they can sprawl all over the place. When it comes to watering them though, you only need to water near the root of the plant. Watering along the sprawled stems and fruit won't actually do anything.
I use plastic bottles to make it easier for the water to go directly to the roots. Below are some bottles where I've taken the label off.
Remove the caps, then cut them roughly two thirds of the way along the bottle.
You end up with two pieces. On the left is the section that you'll be using for the cucurbits. On the right you could cut a couple of holes in the bottom and use these as pots to sow seedlings into.
You then want to dig a small hole next to the root ball of your plant. Not too deep, c. 10 cms. Basically, one-third of the plastic bottle (the thin end) should be embedded into the ground.
This shows that the plastic is in place, with the soil pushed hard up around it to keep it in place.
You can now easily water the roots of the plant via the plastic bottle access.
Here you can hopefully see that I've put in a plastic bottle next to each of the three plants, two pumpkins and a courgette.
Ideally, do this when you plant out your cucurbits, but as I did, you can do it a bit later. Just don't leave it too long, as you don't want to disturb the roots too much.
It's kind of less of an issue in a small garden when you are only growing a few plants, though even then, I've found it means I water more carefully. In a large garden or on an allotment site, this makes it easier to see the where to water.
P.S. I cannot claim that this was my idea originally, but I wanted to share how I do this, with pictures, to show people the steps.