Instructions:

PC: Right click on image and select 'Set As Background' or 'Set As Wallpaper'

MAC OS X: Right click on image and select 'Set As Desktop Background' or 'Use Image As Desktop Picture'

iOS: Hold finger down on image until menu opens and tap 'Save Image' then open the Settings app and go to 'Brightness & Wallpaper' tap the images below Wallpaper then locate the wallpaper then tap it and then tap 'Set'