My dad is 90, so he has to have a stick of some sort to walk in the woods..., so his walking stick is a DIY monopod. He probably would like a Trigger Stick, but since he already had a walking staff...,
I have an older friend who hikes with a hiking staff, and carries his rifle slung when hunting. He uses the staff for part of his camping shelter, and..., he also uses it for a DIY monopod.
Basically a DIY monopod is you grip your hiking staff with the left hand when you're a right handed shooter, and while standing you lay the forward portion of the rifle over top your left wrist to get a stable situation and sight picture.
I just put the palm of my "weak" hand against a tree and lay my rifle into the crook of that hand's thumb and first finger. Works well enough for me...
Whatever works for you is good, and whatever gets in the way is not.
LD