If you’re having trouble seeing the distinctive thorax side pattern, try to match with these alternative distinctions.
Southern Hawker/Blue hawker (Aeshna cyanea)
Southern Migrant Hawker/Blue-eyed Hawker (Aeshna affinis)
Migrant Hawker (Aeshna mixta)
Common Hawker/Moorland Hawker (Aeshna juncea)
Hairy Dragonfly/Hairy Hawker (Brachytron pratense)
Azure Hawker (Aeshna caerulea)