Every once in a while, after I've been wearing a lot of polish without any breaks or if I've been particularly hard on my nails, I'll take a few days to let my nails recover. Everyone has a different method of getting their nails back to healthy and pretty but this is mine:
I start by trimming my nails down to basically nothing. Moving put a lot of stress on my nails so they were soft and cracking. Removing all the damage is really the only way for me to keep my nails from cracking even more. Next, I do one coat of Essie's Grow Stronger. I don't know what's in this stuff but it really hardens my nails and prevents cracking and splitting. Some people will remove it and do a fresh coat every couple of days but I don't think it's necessary. I just leave it on for a day or two, remove, add a fresh coat and then manicure. Another essential product for me is Burt's Bees Lemon Butter Cuticle Cream. Honestly, I dislike the scent and the texture but it does the job and I can live with it if I put it in overnight.
I usually give myself about 3 days for this. I like to have a little length because the initial trim is a little short for my taste. I also like to take the time between the first and second coat of Grow Stronger to give my cuticles a little care. I never let my nails get to the point where I feel like taking a lot more time off from polish would be necessary. With the right amount of care as I go, they never get that bad.
I hope this helps you! I find that it seems like a lot of nail bloggers just swatchswatchswatch and I always wonder if their nails actually look nice under all that polish.