Activated Wyeast Yeast 'Smack Pack'

My first Flanders red ale was the first time I used a Wyeast 'smack pack' or any liquid yeast for that matter.  It made me nervous that the 'smack pack' didn't inflate very much. I had purchased the yeast sooner than I should have and this may have been the reason for lack of inflation, also I might not have waited long enough for it to do its thing. I made web searches using phrases like "smack pack inflation", "wyeast activator swelling", etc but I couldn't find any images. I found text descriptions of the inflation disappointingly vague, e.g. "you'll know." While "you'll know" is a very factual statement it didn't help me much when I "didn't know." Below is an image of activated / swelled / inflated Wyeast activator 'smack pack' versus one that hasn't undergone the change. I would have found this useful.

It's coming out of its shell.

 Note: the yeast on the left (Wyeast Lambic Blend 3278) is the same one I had trouble with before. It had been smacked at the same time (~ 4hours) as the one on the right (Wyeast Roeselare Ale Blend 3763). I didn't wait to see if inflation would occur and ended up mixing the two together. Unfortunately I have been too anxious to see if it is 'good' either time I have used it.

Update: So, um, maybe there is a video on the Wyeast site. I hope it wasn't there forerver.