‘Not a vintage year,” came the usual grumbles about the Glastonbury lineup when it was announced in March – and it’s perhaps only in England where people would moan about the lack of quality on offer at a festival with more than 3,000 performances across five days. In reality, Glastonbury remains stacked with varied, progressive, boundlessly vital artists, and the real challenge is picking your way through them: here are some of our tips.