If you have got yourself into a position where you have to play from thick rough when out on the golf course, your priority needs to be to get the ball back into play.
Being too ambitious in this situation can ruin your round by resulting in a big number on your score card.
To escape from the thick rough and get your ball back into play, use a lofted club, like a sand iron or pitching wedge. Play the ball from the middle of your stance and open the club face slightly, turn the handle of the club to the right. Do this to allow for the fact that the thick rough may grab hold of the hosel of the club and therefore slow the movement of this part of the club down, rotating the club face more left than it originally started. As the thicker grass may grab hold of the club as you play the shot, hold slightly tighter than usual to keep hold of the club and prevent it from coming out of your hands when playing the shot.
Place slightly more weight on your left foot and work on swinging steeply, with a 'V' shape feel to the movement to give the club head a sharper and steeper angle of attack back down to the ball. This will stop the club from getting stuck in the grass before you strike the ball or from hitting lots of grass which will take the speed of the club head and as a consequence, will not move the ball forward enough.
Move the club away from the ball in an upward movement rather than using a low takeaway and work on rotating your body through the strike to allow you to use your body rotation to force the club through the rough.