Besides the good advice about practice, etc. I'd add:
Looking is much easier than walking. Never forget this. It is also more productive unless you are skilled in the "sneak-hunt."
I'd take the .300 WM just because it gives you so many more options. May be way "overkill" (no such word, BTW) but will allow you to take a longer shot if one's presented.
Depending on terrain, I'd most likely leave the scope at 3X (dialed down to 3 in case a close shot presents itself = better field of view in the scope). For a longer shot, you'll likely have the time to dial up to 9X.
After initial scouting to see what the deer are doing & where, I'd hang out on a ridge (just below so you don't skylight yourself) with a decent field of view (& decent deer movement - always helps
) & just sit there all comfy & watch nature unfold. Can get very boring at times .... YMMV - but can really produce.