Yeah, keep a jam jar with you, covered in brown paper with water in it, and jam underneath the lid, with a little hole in it - so the wasps go in after the jam, then fall in the water and drown. That'll distract 'em.
Citronella oil deters most insects but people might think that you have taken up specialised smoking. Wasps don't sting unless they are angry so don't make them angry. Making a wasp killing jar just attracts more wasps and flies so just be gentle and kind to them and they will reciprocate similarly.