These tips are just the highlights, of course. And some may feel other facts may deserve top-nine status. We welcome your suggestions. To get more detail on a particular skill, position, or situation, click the top left diamond dots.
1Left foot on the bag
The most important step for a second baseman or shortstop to remember. By planting the left foot at the back of the bag, the right foot is automatically safely behind - well away from the sliding runner. As soon as the ball is at the glove, pull the left foot off. (Shortstops should also still work on the drag step with the right - it lets them clear the lane quickly.)
2 Straight-arm toss  
Important for quick shovel tosses around any bag - for all infielders, including pitchers. Grip the ball with lots of white showing. Straighten throwing arm towards bag. Aim chest high right at the glove. Keep wrist stiff on release.
3 Know the fence 
For catchers, first and third basemen, left and right outfielders. Feel for the fence with your throwing arm, or do a slide catch (drop down like a foot-first slide into the bag. (Test the warning track before the game - count the running strides - so you know when to slide.)
4 Stride to your spot 
Pitchers should work on landing in the exact same footprint on each throw home. When the lower body is under control, the top will follow right through release point. Hitters can benefit from being as consistent at the plate. Step to the same spot and your head won't drift.
5 Tap your heels 
Balance is key, for fielding, throwing, hitting, running. The simplest, quickest way to test if you're properly balanced on the balls of your feet - tap your heels twice - both together. It won't force you onto your toes, but it will keep the weight forward.
6 Eat right
Game day snacks: Bananas, yes (for muscle toning) and oranges, yes, but apples, no (too much fibre). Fluid replacement: A 2% drop in hydration = a 10% drop in performance. Water, please, no pop or coffee. (They're diuretics - you have to drink a glass of water just to make up for what the pop has taken.)
7Weights & Toning 
Lift for power not just strength. Better to do reps and sets with lighter weights and a fuller range of motion. Slow is better. Cool down stretches and wind sprints are important for quicker muscle recovery. Solo Ball is a good time to work on this.
8 Back foot curl
This works for throwing - and for hitting. Don't try to push off your back foot, just roll forward on the inside edge. This curl will bring the back knee in and turn the hips out - good for generating bat speed at the plate and shoulder speed off the mound (or in the field).
9 Swipe tag 
So simple, so often forgotten. Always make sure every infield drill includes swiping the glove right across the bag. Never freeze the glove to give the umpire a freeze fram that's after the fact. You want to show that you got there first.