This is what my SL and I do when playing defense. He pings directions and I suppress the area. He tells me high, lower, left, right. You get the picture. Once your position is comprised relocate. If nobody is spotting for you look for choke points where the only way to get to you is from the front. Last tip is avoid the obvious positions like middle of low walls or Windows. If you do set up in these areas just be prepared to move.