I'll keep practicing then, it just gets tiring is all.
When I first jumped into AH I always upped in the area that we were most outnumbered, thinking that would be the best way I could help my country; by starting to even out the odds in those areas. That meant I was always fighting outnumbered. It didn't matter to me what the odds were. I knew I could affect the outcome of the war by focusing the enemy on me. Along the way I got to a point that I could win almost all 1:2's, most 1:3's and an occasional 1:4. Anything more that that's just attempting to survive and distract the enemy. Anyone who tells you they can consistently beat odds of 1:4 or greater is lying. At least they're not doing it by scrumming in the dirt like I typically was.
Later I went through phases playing for score (I was consistently a top 10-50 player overall) and phases flying every plane in the plane set until I landed multiple kills in each (I did several rotations through the plane set like this).
Now I mostly play for scenarios but for a long time when I upped in the MA I didn't know what to do. I had no set objective like I always had so I went back to my earliest days of trying to even out the odds. There's nothing like staying alive in a 10-20 on 1 and making the opponents think who's that?
Here's a few things I've learned over the years, many of which have already been stated:
1. Know everything there is to know about the plane you're flying.
2. Know most of what there is to know about every plane in the plane set.
3. Maintain altitude to the best of your ability.
4. Manage E effectively so you can go vertical if you have to.
5. Keep your head on a swivel. The one con you didn't track will kill you.
6. Never stop maneuvering, even for a second.
7. Don't saddle up unless the opponent is always maneuvering and then, only for a second or two at most.
8. Be unpredictable.
9. Think two to three moves ahead. Plan, Execute, Evaluate, Adjust, Execute... never stop.
10. Stay skinny. Give them a side profile just as they line up for the shot. A side benefit is being able to roll the opposite direction for the overshoot.
11. Kill targets of opportunity (crossing shots, high deflection, high lead turn shots, overshoots...). Defense first, offense second, always.
12. Try to coax bigger threats into becoming targets of opportunity but don't lose sight of the bigger picture.
13. Kill quickly and effectively (in the most difficult situations to do so).
14. Keep everyone in one view if possible (I prefer front quarter).
15. Don't worry about score. It won't look good.
If you can do all those things you can effectively manage a multi-con engagement but don't think it will come easily and without pain.
Now let me tell you about the day I killed five Brewsters in my Spitfire...