There’s a few ways to minimize ladders, though sometimes they even out when you wash the mittens. If you use dpns, maybe switching to 5 needles will help; with circs, if using Magic loop, you may need longer needles and going to a single loop will work better. You can also rotate the stitches on the needle - when you finish a needle, instead of switching to an empty one, knit a few more sts onto the R needle, then switch. If you do that every 2 or 3 rounds, it keeps the split between stitches moving around so it’s not at the same place all the time.