As others have mentioned, the burn of the solid propellant used can't be controlled. However, you could look at things like gyros, thrust vectoring or servo co

As others have mentioned, the burn of the solid propellant used can't be controlled. However, you could look at things like gyros, thrust vectoring or servo controlled fins to give you more a more controlled ascent. That wouldn't help with the descent which is traditionally unpowered. Maybe a small charge to flip the rocket around and then use servo fins to control its glide direction on the way back down.