Border on C2C

[Hookalong]

I've just finished my first ever proper project a C2C blanket. I want to use all four colours in a border.
It's a little loose, holey and stretchy, next time I'll go down a hook.

How do you all start a border on a C2C?

I've watched so many YouTube videos on how to attach the border. The most common method seems to be DC in the gaps and chain2.
I've done half way like that and it looks nice enough but I wonder if I need something a little tighter for the foundation row?

I have found a really nice edge that goes well with the c2c pattern. Only one row as well. It is similar to what you have done but do 4 chains after the dc then put 3 tr into the first chain before the next dc. It makes a triangle border that matches the stitches really well. Like a row of upside down vvvvvv shapes. Hope this makes sense x

I tend to keep it simple or go completely overboard with the border, usually go overboard if it's a plain white blanket in a light weight yarn but the simple one I like is from The Patchwork Heart.
www.thepatchworkheart.co.uk/2015/08/corner-to-corner-blanket.html?m=1