To Buy: 
Try to find coriander at an Asian store as they seem to select the youngest, freshest bunches. Look for a light, bright green colour and smell the roots for the distinctive aroma, and avoid bunches with limp, drooping leaves.  
To Store: 
Store in a plastic bag lined with damp absorbent paper in the fridge. It will keep this way for up to 5 days. 
Tips & Tricks: 
Wash and dry thoroughly. Remove the leaves from the stalks. Cut carefully with a sharp knife to avoid bruising the leaf. Add only for the last couple of minutes of cooking, or sprinkle over as a garnish.
Cooking Tips: 
For a more concentrated coriander flavour peel the coriander root and crush it with a large knife. Add to stir-fries and marinades.