Alright so I know there are already a couple threads/builds that have explained how to remove the front bumped on 2015+ Colorado.
I thought some would like a detailed step by step with pics.
I removed my bumper to install some aftermarket fog lights, which you don't necessarily have to do but I was also going to paint the grill and some other stuff so made more sense to remove the bumper.
You can also follow this to have access to all the hardware on the air dam. You could then take it off or switch the clips for easy access from below for quick take off/on.
What you will need:
T-15 torx bit (shorter the better)
A ratchet to fit said bit (I used a small 1/4in ratchet)
7mm socket (again 1/4in drive)
10mm socket (1/4 drive or adapter needed)
6+in extension for ratchet
A flat head or something for fog light covers
Something soft to lay the bumper on
It also goes to say, you can follow how I did it or improvise yourself as needed and I am not liable for you messing anything up or breaking anything. Be smart.
I completed this on the ground without lifting the truck or turning the wheels. With a small ratchet and bit it's completely doable but if you can't fit between wheel well and tire you made need to turn wheel or lift front as necessary to access underneath.
Remove the T-15 screws around the top of the grill, there are 6 of them (red circles)