Armor, Shield, Footwork, Variety, and Hilt Blocking.
Armor: Having armor is a definate advantage. Lets say you two square off and are at full health/armor. You go for a sold hit on his shield (One!!) He starts his charge. But that first shot just went into the first. This time on the shield again, and then maybe towar the right side.
(If he was fast enough, then he might have gotten your arm only once in this exchange. (But alas..."Arm armor")
Also, lets say if the person you are fighting is a calculatory fighter. (One that analyzes you, then attacks. Then if you catch them off guard, then you can go in pummeling, and you might get them off guard, and you can keep hammering away. (One way to assist in this is to get to him when he is fighting someone else (The third to last fighter) This way, his attention is divided.
Shield: A buckler will help. You will be archer bait with a red, and it provides incidental blockage during your swings. (Harder to control while swining a red.)
Footwork: Stay mobile. You may need to backpedal, sidestep, or advance instantly, so stay on your toes. One way to do this is to bend your knees in your fighting stance. You will start to feel your knees shaking slightly from the tension, and that will make you a veritable spingboard.
Variety: Throw a variety of shots. Get that shield shot, or one handed leg shot from long distance. Normally when a person takes that first shield shot, they will get worried because they don't want the second, so they will move in.
Other than that, throw a shot at the shield, then go for their sword arm on the other side. If it si a punch shield, pummel the top of the sheild and drop one in on their shoulder.
Hilt Block: They swing, you block with your hilt or blade, then counter swing on their attack arm. Example, when fighting red to red, block and counter swing is one of the prime methods of fighting. Against a sword and board, then you have to move quicker becuase they can reset their shot faster. So let them hit your sword, then counter swing.
Overall, I found that practicing against red swords, esp. against fighter who will "hurt" me
forces me to step it up, block and hit. Then as your speed increases, then your shot delivery will increase....
Good Luck