I have explained translating a WordPress theme in your language without any plugin in some easy steps. You can catch up from step you are reached at if in process already.
Install WordPress in your language
To translate a theme you have to have a WordPress installed in your language or you can change language of already installed WordPress from Settings > General > Site Language. To install WordPress in your language visit this link.
Editing PO file
All themes published by Majestic Themes are fully translation ready. If you are trying any other theme then make sure it is translation ready and have related files.
You have to find default.po or file name similar to theme slug like ‘majestic-recipe-press.po’ file from languages directory of the theme. If there is no such directory then find .po file on root of them theme.
After reaching to the file you have copy and rename it to your required language name following the language translation rules. Like for french language your file should be fr_FR.po. You can find complete list of codes at Country Codes or Language Codes.
Translating .po file
You need to have an app or software to edit your .po file and translate it to your language. For local i recommend POEdit which is very easy and popular tool to do this. You can also try following online tools to do so.
Once you open the file in app like poedit then you can translate it word by word and then save it.
Uploading the file
After saving the file using poedit tool you will find a .mo file in same directory you saved it. You have to upload both files in same directory you have downloaded it from. After following all these steps your translation should be working fine.
Translating from Child Theme
If you are using child theme to customise your theme and translate it then you have to put these files in child theme’s languages directory instead of parent’s. This way you can easily update your parent theme without any trouble.