[HappyHippy]

why dont you try and work him a wee bit? shetlands are triple purpose after all and it might be fun.

What could I get him to do ? and how would I start - is it the same as with horses ?
Interesting stuff 

[Rosemary]

Shetland cattle were traditionally triple purpose - draft, meat and milk. There's a book published by the SCHBS called "A dander trowe" that has photos of Shetland cattle in harness.

[scarlettoara]

yes, you get them to pull loads or plough the field. if his temperment is placid, im sure he'd let you have a go.
would be fun to find out. 

http://tillersinternational.org/oxen/resources_techguides/YokingandHarnessingSingleCattleTechGuide.pdf