I use 100% pure tung oil from Woodcraft, at about $20 per quart. A little goes a very long way and it oxidizes in the bottle, so squeeze the bottle or add marbles before closing to keep oxygen out. One quart lasts me over one year of building small furniture, wall and mantle clocks, music boxes, etc. It is beautiful with walnut or cherry, and gives a nice flat finish with hard maple.
It is rather thick, so I usually dilute it 50/50 with mineral spirits. I rub it onto a smoothly sanded surface (minimum 220) with a wad of XXXX steel wool. Dull spots need more oil, as it has all been absorbed by the wood.
After about 20 to 30 minutes, it will start getting sticky. Wipe it all off with a polishing action with soft, absorbent cotton rags. If it is getting too sticky, quickly rub over the oil with more mineral spirits to slow curing.
It will be dry to touch in an hour or two, won't collect dust, but has not yet cured. Add more coats at about one day intervals until you like the finish. The finish will be deep but flat. When I prefer a little gloss, I mix about equal parts tung oil, oil based urethane, and mineral spirits for the final coat or so.
The resulting finish is easy, beautiful, and durable, but won't be fully cured for about a month. It can be handled when dry to the touch, but might stain a carpet or table cloth until fully cured. If any "sweating" should occur while it is curing, just polish it off with a clean rag. The finish is durable, and easily rejuvenated if ever needed by doing one more pass with tung oil and mineral spirits. Do not use household furniture polishes, as they may make the finish turn milky over time.