If you are collecting subscribers to make money and email them, you need an autoresponder. I'm not familiar with Jetpack, but I suspect that it's only getting subscribers to your blog, which is something different from building a list.

To collect subscribers, there area lot of things you can do. HUNDREDS. But they all revolve around traffic! Without traffic, you can't collect emails.

The simplest thing would be just to have a central "squeeze page" on your site where you collect emails, and then you direct traffic from blog posts to your squeeze page.

Are you blogging on a regular basis like the WA training suggests?

Ill give you my suggestions...they work brilliantly for me...but there are many methods...this is just the one I use.

Firstly...ditch Jetpack...it will seriously slow your website and adds lots of glitches, errors and bugs. There is very little use for it...it looks great with sooooo many functions but in reality you don't need them and the slow load time will lose you traffic.

Add SumoMe Plug in...this adds several brilliant features. You can see training about it below... SumoMe! Analyse, Grow subscribers and traffic with 1 simple plugin! SumoMe Share - Are You Utlizing All The Features? For collecting email subscribers install the SumoMe apps - list builder, scroll bar, welcome mat etc...this will give you subscriber functionality.

Then set up an autoresponder service. I use aweber...but it does cost (however you can try it free for a month)...try mailchimp...its totally free until you get 2000 subscribers or getresponse (getresponse is free trial for month but has some of the best list building training available)

Once you have both set up you can link sumome to aweber/mailchimp/getresponse....

Hope this helps
Jason