You can bareshaft tune woodies, but I don't, and wouldn't recomend it. Especially while you're new to 'em, and still working on form. Tried it a few years ago, and haven't since. 90% of my tuning is by eye. Shooting a broadhead from 20 yards or more tells me plenty. Once in a while I'll shoot a few holes in paper (with field points) if I want to get technical.
Spine will depend on your bow design, depth of center cut, your draw length, desired arrow length, and preferred point weight. String type matters a bit also. If you know those specs, we can get you mighty close for spine.