Customs via Scanned Template

Hi all,  as you may know, I have designed a few templates & as yet they are all blanks.  I am experimenting in illustrator & watching online training video's so my knowledge is starting to pick up.  I would however like to pick your brains for tips on scanning in templates.

I am soon to get a scanner, & have no trouble hand drawing design's on to a template and scanning it in.  At this point though my learning curve flattens out a bit.

I'm asking for advice & tips on the best way to change the scanned in image on screen into a digital template.  Do I have to use just the pen tool, or will live trace do it well enough.  Apologies for being a noob in this.

Also, any illustrator guru's, can answer me 1 further question.  I have been trying to open my current templates in AI, but when it opens, the worksheet is on the screen with about 2% of my template on it, and the rest is way off, as if it's made it sooo massive. :(  What am I doing wrong.. Im guessing it's a basic error.

Thanks in advance.