Flash Technique...

I am learning to use flash, I have a 5d2 w 580ex2 mounted on the hotshoe.

Today I was photographing my baby using the flash, I was in single shot mode but snapping rapidly. The flash kept up for the first couple of shots then no more flash (recharging I suppose) if I waited a moment again I could get 2 shots in a row with flash. If I really snapped quick maybe 4 shots with flash. If I tilted the flash I could only get 1 shot in a row with flash...

This was all in ETTL, when in manual and dialed back to 1/8 and tilted, I figured for sure I would get more flashes in a row but no, just one and the next shot it would not fire...

So I need some advice, in a setting that requires quick grab shots like shooting a baby or event what is the best technique to avoid taking a shot without the flash firing?

it varies because ettl judges how much power you need for every shot, if you were trying to bounce the flash (pointing up or tilting) it tends to use more power because you are spreading the more light around to get a softer look.

Direct flash tends to recycle faster due to teh fact that the light is not wasted and directed toward the subject.

The 580EX II should have some very quick recycle times.

Opening up your aperture and increasing ISO allows for lower flash power, and therefore quicker recycle times, so give that a try as well. Also, check to see that your batteries have a good charge, as they drain, the recycle time of the flash increases.

Fresh batteries, most rechargables discharge over time while stored so they may have less in them than you think. Also shoot with a higher iso if possible so your flash has to do less work.