Kicks to the back are usually illegal. Kicks to the head require a high chamber, use a lot of energy, are easily blocked, and the head is a difficult target to hit, so they are used judiciously. Therefore most kicks are to the abdomen. Side kicks to the abdomen are rare since the abdomen is usually angled to the side, so most side kicks are to the lower ribs on the lead side. Since this is the most used target, if you want an opponent to fire a side kick, raise your lead arm so the high elbow exposes your lower ribs.
When fighting in an open (opposite sides forward) fighting position, if you want the opponent to fire a lead hook kick, keep the lead elbow low to protect the ribs, and either lower the rear arm to expose your head or raise it to expose your abdomen.
When fighting in a closed (same sides forward) fighting position, if you stand in front of your opponent, you are a target for most all kicks. If you move to the sides, the easiest kick for the opponent to use is a round kick. Therefore, if you want an opponent to fire a round kick, move the sides and expose your abdomen.