Thermacell won't work on ticks.
You need to use permethrin sprayed and allowed to dry on your pants legs waistband, and shirt cuffs and collar area.
That's the only way to eliminate ticks.
Osage, yes...I've had really good results with thermacell...they say lay flat... but as long as you loosely attach it so air can get to the back of the unit, you're golden.
I hang it from a pack, possibles bag strap, or my belt behind me. The stream of repellent trails behind you if you are moving- that's exactly where your carbon dioxide trail is, which is what the mosquitoes are following to locate you so they can get a meal.
As soon as you become stationary, the protection surrounds you. If there's a breeze, you don't need to worry too much as skeeters anyway because they'll go down in the grass/bushes to escape the breeze to begin with.
We have the duck-raper subspecies of mosquito in SC and I don't wear any repellent- just use the thermacell and cover up sensibly- long sleeves and no exposed neck area as I use a kercheif or other neck covering and a hat.