Honestly, start building skills that are directly related and demonstrable by building a portfolio of games. Go learn Unity 5, or Unreal Engine 4, or Cocoas-2D, or GameKit, or MonoGame, or anything really -- as long as you can use it to develop and showcase your skill at making games, you'll be moving in the right direction.
That said, design positions are a rarefied role in an already rarefied field in an already rarefied industry, and one which is extremely competetive with no shortage of young brainiacs willing to work 50-60 hours weeks for relative pennies on the dollar. I don't mean to be discouraging, but that's the reality of the situation. You may not posses the health, or the youth, or the willingness to give up a significant amount of personal time to be competitive, and you might have life-circumstances (e.g. people to support, debt, etc) that would be serviceable with a typical entry-level games industry wage, or much less as an IT monkey.
The upside of being alive today, though, is that there are avenues for dedicated, talented people to make their own way and break into viable markets like Steam or Xbox Live, or the Playstation Store. That's no cake-walk either, and far from guaranteed (or even likely) success, but its a shot you can make something of if you put in the work and have the vision.