FOLLOWING ALONG WITH THIS MIGHT GET YOU PARALYSED, GO READ A BOOK ON LACTO FERMENTATION
With that out of the way, I'm sort of adapting The Noma Guide to Fermentation's blueberry recipe with strawberries.
I took about 250g of strawberries which were getting a little old after Christmas, trimmed the tops and ended up with 200g of strawberries. In a bowl, I added 2% of the weight in salt (with an extra pinch or two for good measure). After a good stir around, I scraped them into a spring-top jar and weighed them down with a ziploc bag full of water inside another ziploc bag to prevent leakage.