My site is up and running for about 6 months and i've been building backlinks to the site for the past 2 months.
However, i've decided to change the site from non-www to a www website. The only reason being is that i think it looks better in the SERPS to have a www before the website. it looks more professional in my opinion.
What i want to know is after i've changed the .htaccess file and set my preferences in google webmaster tools etc, what will happen my SERPs?
Will they disappear and have to be re-indexed all over again or will they slowly change from the non-www versions to the www versions?
It varies and can take anything from a few days to many months. You'll likely see a dip in traffic to begin with. The new URLs usually start to appear within days, and it takes a few months for the old ones to drop out.
One important question. Will you be reversing a www to non-www redirect, OR have you simply been linking to non-www with NO redirect in place and now you are going to link to www AND place a non-www to www redirect at the same time?
Whatever you do, you must change the links on the pages so that clicking any internal navigation link never results in a redirect.
At the same time, make sure you're linking to "/" or to "/folder/" and NOT to a named index file. Install the standard "index" to "/" redirect too (it goes before the non-www to www redirect).
These searches are useful: site:example.com -inurl:www site:www.example.com Make sure the site root is the first result in the list.
"One important question. Will you be reversing a www to non-www redirect, OR have you simply been linking to non-www with NO redirect in place and now you are going to link to www AND place a non-www to www redirect at the same time?"
Yes i will be re-versing an initial re-direct i had done. The site initially was available at both the www version and non-www version. I decided at the time to direct it to the non-www version. However having now seen what it looks like in the serps, i'm starting to think would i be getting a better ctr in the serps if the site had a www before it. I know this is only a small thing, but i intend putting a lot of effort into the site so i want it to be right from the start. Also, i think it's already linking to "/" as you say (though i'm exactly sure what you were saying). At no place in my google webmaster tools/analytics does it say i'm linking to an "index" anyway.
Is it safe to mess with the serps like this? I mean, could ascraper site scrape my site in the middle of the process and lay claim to the content i do have up? and thus ruin the work i've put in to date?
looks better in the SERPS to have a www before the website. it looks more professional in my opinion
That's your judgement to make, of course, but know that not everyone shares that opinion.
starting to think would i be getting a better ctr in the serps if the site had a www before it
Is this something you've actually tested, or is it just a gut feeling on your part?
Suggestion: before you make the change you're considering, do some testing with pay-per-click to compare the CTR you get both with and without the www. in the display URL. That might tell you something useful.
Something else to consider is the effect on social media. Staying with the shorter version would make it a bit easier for people to tweet your links.