Complex sentence: Warpaint were on tour in Europe in the spring and this summer of 2011 to promote the album: they played at various major festivals including Glastonbury, Reading and Leeds festivals and Rock Werchter.
Split into simpler sentences: Warpaint were on tour in Europe in the spring and this summer of 2011 to promote the album. They played at various major festivals including Glastonbury, Reading and Leeds festivals and Rock Werchter.