Nothing is easier or cheaper to keep clean than floors, but the how-to always seems to be problematic. I've cleaned people's houses for 18 years, and did offices for a professional cleaning service before that. Here's what I've learned:
Dish soap does the trick. Even very diluted, say, 1 tsp in a bucket of mop water, it will help a lot toward cleaning the floor. If the floor is very dirty, sticky, or greasy, make it a little bit stronger. Don't worry; it will all come up, and easily. Use straight hot water. Don't wring the mop as dry as possible for this go-round; the dirt has to be kinda wet in order to dissolve so you can pick it up with the mop.
When that's done, pour out the dirty mopwater, and this time refill with clean water and 1 c of any vinegar...the cheapest you can find. Mop again, this time wringing the mop as dry as possible. Vinegar cuts the soap, and so while you're picking up the dissolved dirt, you're also rinsing any detergent residue off of the floor. With wood floors of any type, dry the floor afterward. Actuall, drying the floor is a good idea no matter what; it gets up the last of anything that could be left behind to show streaks.
Test any cleaning method this way: After you've cleaned and rinsed the floor wipe it again with a damp white cloth. If your cloth doesn't come out clean, the floor isn't clean. Simple as that. Streaks come from detergent or dirt residue; get the floor really clean and there won't be any.
Denise from Ark