The images below show the best mounting positions for Milo based on your gear and activity.
In general, you want to mount Milo as high up and close to your mouth and ears as possible. Also, you want to keep Milo unobstructed, so don't put Milo in your pocket.
To minimize noise, like from skis cutting into ice, mounting Milo on your front is usually better than on your side. High up on your shoulder is usually a very good location.
If you have a pack, you can use the Milo action clip to attach to the pack straps.
If you don't wear a pack, you can use the Milo pocket clip to attach to the zipper on the front pocket of most ski jackets.
If you don't have a pocket clip don't have a good place to fasten an action clip, try using the long lanyard that comes with your Milo. (You can swap that out with the one that is pre-installed (Lanyards: How do I change them?). Find a way to hang it around your neck and then use the length clasp on the lanyard to remove any slack and keep Milo right under your chin.
Some people like wearing Milo on the side of their helmet or goggle strap. The benefit is that it keeps the Milo high and close to mouth and ears. The potential drawback is noise if you're a faster skier than some of us. :)