From Smart Job Board help
ShareThis feature allows your users sharing a page content with others via e-mail, Facebook, Twitter, Yahoo, etc.
The widget it located at the bottom of a front-end page, for example Job details page:
To set ShareThis feature go to Admin Panel >> System Configuration >> Plugins. Click on the "Settings" link opposite the ShareThisPlugin in the table.
The ShareThisPlugin Setting page will be opened. There you can see the ShareThis Button code:
This code defines the type and style of the ShareThis button used on your site.
As the comment says, to change the type and style of your ShareThis button you need to receive another code. Instructions to do that you can find here.
Below the button code you can see the following options:
Check/uncheck the boxes to enable or disable ShareThis widget display for News, Job Details and Resume details pages or for All Pages of the site.
Make sure to press the "Save" button to save the settings you made.
To get a code for a ShareThis button with different type and style, go to http://sharethis.com/publishers/get-sharing-button
On the opened page go to the option #2 "Choose a button type and style":
Select a desired Type for your ShareThis button. And then select a Style:
Once you selected desired type and style, press the "Get the Code Already" button at the bottom of the page:
Then if you're not registered and logged in to the site you will need to fill a short registration form:
Enter the URL of your site to the Domain Name field and enter the desired Email, Username and Password.
You will be able to use this account in future if want to get different type and style for your ShareThis button.
Once you have registered you will get the code of the button with the type and style you selected:
You simply need to copy the code from the first box and paste it to the "ShareThis Button Header Code" field in the ShareThis plugin settings in your Admin Panel.
And copy the code form the second box and paste it to the "ShareThis Button Code" field in the ShareThis plugin setting.