I use three wooden boards daily, and one is quite large. Here are all my tips and things I do:
First, with each board, when I first got it, I followed the old cook’s tale of “once a day, once a week, once a month, once a year,” meaning I oiled it once a day for a week, then once a week for a month, then once a month for a year, and now whenever it feels a little dry or looks like it’s absorbing water.
I use food-safe mineral oil, buying it from the pharmacy (where the laxatives are stocked). My sister swears by super-expensive beeswax. I’ve used that and it’s too much work for me, costs too much, and has the same results.
Day-to-day cleaning - if I’m just chopping rather benign vegetables, or kneading bread dough, something like that, just a quick scrape with a bench scraper and a damp cloth, but if it’s anything oily-greasy, or if it’s anything that stinks, like onions or garlic, those get dealt with and into a prep bowl immediately, and a quick wipe with a damp paper towel before I move on to the next item. Apparently, my superpower is that I can smell old garlic or old onion odors on a board for weeks if I don’t do that (and I’m prone to giving my board a whiff when I walk by it from time to time, just to make sure all is well).
Chopping stuff like that, as soon as I’m done with it, into the (empty) sink (no submerging), then a good scrub with hot soapy water, rinse, dry with a towel, and then propped up at an angle so it can dry evenly all the way round - some boards, depending on their material, size, and construction, will begin to warp over time if left to dry flat.
If I’m quartering a lemon to juice, I’ll usually take that as an opportunity to rub the spent quarters over the board, as a natural cleanser-deodorizer, letting it sit for a bit, then wiping it off.
Heavy-duty cleaning, if I’ve gotten something particularly noxious on there, I’ll make a thick paste of baking soda and water and leave that on for a while, to really pull the odors out. I rarely have to do that.
All in all, I treat it like anything else in the kitchen - if I use it and it gets dirty, I wash it.
There are a lot of buying guides out there for chopping boards, too, so read a few of those to make sure you know the pros and cons of different woods and different construction methods. It makes a difference.
