How to track a sale back to the initial visit in Google Analytics

Question

How do you track sales in Google Analytics from the initial visit?

I make most of my sales when I promote my products via my list, but when I check the stats to see where the initial visit came from, whether that was a day, a week or even a month ago, it doesn't show the sale.

It only shows a sale from the most recent visit to my site when the sale takes place.

Is there a solution to this?

At the moment, I can only see if a sale is made if it comes from one of my email lists, or through one of the pages on my website (not from the initial traffic source)

Would be great to know which traffic sources are converting into sales!

Update

Thanks for your response. I am currently using URL's this way, but only with utm_source, utm_medium and utm_campaign. For example, for traffic from a Facebook group, I might use a URL like...

http://www.example.com/?utm_source=facebook&utm_medium=facebook_group_123&utm_campaign=myblogpost

Should I be using more parameters?

Now for those who visit my site first time and sign up for my free guide, I can track all these visits and know which traffic sources are best for opt ins (by creating a goal in analytics and using a 'Welcome' or 'Thanks for signing up page')

But for sales, I create another goal, and it only shows a sale if it comes from their second, third or more visits. For example, if there's a link to my product from my 'Welcome' page, I might use a URL this way (because I want to know which pages on my site are also converting best for sales)

http://www.example.com/welcome?utm_source=mysite&utm_medium=welcomepage&utm_campaign=product_x

However, this is where sales are being recorded, regardless of what's happened beforehand. Does this make sense? The traffic source is being completely ignored for sales

Sounds like I'm doing something wrong with my use of parameters...

Answer 1

Google Analytics expects you to use tagged "campaigns" when you have a traffic source and you want to track conversions back to it.

To make this happen, you make sure traffic from that source comes in on URLs with UTM parameters on them like:

http://example.com/?utm_source=bobs-ad-network&utm_medium=banner&utm_term=site-where-ad-appeared&utm_content=two-for-one-promotion&utm_campaign=january-ad-blitz

When your traffic comes in with URLs like that, reports in Google Analytics will automatically track conversions and other items back to the correct campaigns. Google has a tool for generating these URLS.