I used a lot of reference for this one, this being only one of them. Even though I opted going for a darker color wood, I thought this was a good starting point.
Then I created my base texture, adding some dings and divots to add some character. The grain was one of the harder parts to perfect, but I think it came out alright.
Finally I outlined the floorboards. I made sure to add variation to the length and width of each piece. I then added the shadow and highlight, finishing with a tiny edge highlight and splitting the wood ends.
Again, this should be perfectly tile-able. Let me know if you see something that doesn't belong!