I decided I wouldnt read anyone elses responses as it might deter me from my original thought and action. So here are my answers, sorry for any same answers as someone else. Once my answers are posted I intend to read other answers and those given by the more experienced divers to see what I can change / prevent from my original thought. Btw, Thank you Cave Diver and BubbleTrouble for putting this together. I really appreciate that you are keeping us newbies thinking and learning.
* What would you do if you lost sight of your buddy underwater and couldn't find him/her?
I would look left, right, up, down, behind and do this once again. If I could not find my buddy I would follow the rules given by PADI to look for my buddy for 1 minute, signal that I am going to ascend, and begin a slow ascent at 30 feet per minute with a 3 minute safety stop at 15 feet. Hopefully my buddy will see me, ascend and we could meet at the surface, inflate Surface Marker, determine air supply and if we can continue the dive or whistle for dive boat.
If I dont see my buddy follow while ascending and if my buddy did not surface I would inflate my surface signal and blow my whistle to call the boat. I will let the boat captain know I got separated from my buddy to keep an eye out for him/her. (even though thats pretty obvious to the captain)
To prevent this I would discuss the buddy separation plan with my buddy pre-dive. Also, discuss how often we should look for each and to stay within arms length to 5 feet away from each other at all times in case of an emergency.
* What would you do if you're in a buddy team of 3 divers and one buddy went left while the other went right?
Hopefully I have a tank banger on me, I would bang on my tank to get their attention, regroup, determine a direction, and leader.
To prevent this situation, all people in the group would discuss the dive plan, direction of travel and decide on a group leader and back up leader (in case leader gets tired or looses direction)
* What would you do if you're in a buddy team of 5 divers and, all of a sudden, you only counted 3 other divers in your field of view?
Get the attention of the divers or at least one diver and signal to them by pointing at each diver and signal each diver a number by counting on my fingers, when I get to number 5, I would signal I dont know by shrugging my shoulders (cant remember what the signal is for that atm). Then point to my mask signaling to look and the around sign??? Not really sure how I would handle this situation, but this is my initial thought. Hopefully some good words of advice are given for this one.
To prevent this situation, we would discuss what we should do pre-dive if one person or a pair of us gets separated. Perhaps there should be a buddy team of 3 and buddy team of 2. One buddy team would lead, the other would follow.
* What would you do if you're diving in two buddy pairs and you lost sight of the other buddy pair?
Get my buddies attention (tank banger), signal the number two, signal diver (by holding two fingers horizontal moving fingers up and down in opposite sequence), then signal look and signal around. Hopefully my buddy will know their direction. If not, hang out in this location for a minute or two while searching in each direction (Left, Right, Up, Down, and behind). If the pair is found, follow their direction and if we could catch up, get their attention and signal to the pair to stay together by holding 2 fingers out on each hand and then putting both finger pairs together to show we need to stay together.
If buddy pair is not found, I would assume we follow the 1 minute rule if you lost your buddy (as given in answer 1)
To prevent this we would discuss pre-dive the dive plan, direction and assign a pair to lead. The leading pair should also keep an eye on the following pair in case they stop or change course.
* What would you do if you got a leg cramp but your buddy didn't notice and left you behind?
Stop, keep eye on buddy, work out leg cramp by holding leg straight out and pulling the end of the fin towards my body, keep eye on buddy, relax and breath, work out the cramp and continue diving in my buddies direction. Catch up with buddy and get his attention, show him the signal for leg cramp and then show him the signal to stay together and look for out for each other.
If I could not keep up with my buddy I would probably try to follow at my own pace for a few minutes or until my leg cramps up again and work out the cramp. Hopefully my buddy will look for me and turn in my direction and assist me.
If my buddy doesnt come to assist me or if there is no one else to assist me and the cramps persist I would have to end the dive, signal I will be ascending, ascend, safety stop, inflate SMB and blow whistle for the boat.
To prevent this, I would discuss with my buddy pre-dive that we should check each on each at least every 3-5 minutes. Im not sure if we should be checking on each sooner than this or if this is too often. Also, discuss with buddy that we need to be at least arms length to 5 feet away from each at all times in case of emergency.