How to add an additional language version of your site:
1) Click 'create page' and then choose the 'create new language version'-tab
2) Enter Language name (e.g. 'EN' for English, 'FR' for French, 'PL' for Polish etc.)
3) Choose language from the drop down menu
4) Enter the page URL (e.g. if you created an English version and called it 'EN' in step 2, then you should enter: www.youraddress.com/en in this field.