You have several options, and you should probably start reviewing them because most plants grow for at least the first 21 days into flowering, and some will even attempt to double in size. If she is already 6 feet and you are hitting your lights with no room you might be in some trouble.... ?
1 - you can cut the tallest tops off down to a node level with the other tops on the plant and the buds below will grow bigger.
2 - you could lst or supercrop her
3 - you can begin pulling your plant over on its side, slowing each day pulling the entire plant over on its side until its like an L shape coming from your bucket and all of the tops will retrain and grow up towards the light (this method is huge in colorado right now) its similar to ring around the rosey training if you are maybe familiar with that method. It works best when main stems shoulder most of the growth
4 - let it grow into the light to stop forward growth - it will hit the light, burn, damage and stop growing once you see what will burn and what will stand the light and heat you simply trim the burned areas away