There are so many recommendations on SEO but my question is: How do you measure it? How do you know that your SEO tactics/optimization actually worked? I think one way is to track the amount of organic visitors before and after the refresh. What else do you measure or track?

You measure the qualified traffic compared to your hits.

Mozilla Firefox has many tools for SEO.
The only thing I dont like about this browser is that every day when I open it it installs updates. I feel like they are spying on my pc.

Oh, you better be scared of that Godzilla Modzilla. It's got big big teeth and it can read your mind too...

No No No just joking. I have something professional to add I just can't remember what it was right now. I'll get back to this ... soon.

Take a look at your server log files. Find a way to differentiate your visitors from other automated mambo jumbo.

I think your behaviors on SEO might not reflect on your SERP so rapidly. So, I would like to recommend an add-on for Firefox to be used for monitoring purposes. It would show so many factors when you open your site in Firefox.