I just try to ward camps early VS aggressive junglers. Get your team to group up and invade at level 1 to get a ward onto their buff, preferably after 1:20 inside of the nearby brush. Once you know their start you have a fair idea of what they're doing.
If they start bot side and run up it means they're going to either early gank top or invade, in this case you want to go buff to buff to stop the invade. If they start bot and run down they're clearing, you can get away with a greedy clear if they do this.
If they don't start bot it means they're going top buff to your buff, you should generally try to take their bot buff if they do this, although if you have a really weak clear it's sometimes still better just to allow yourself to be 3 buffed incase they go top buff to bot buff.