Only useful arrows are Silver
Silver Sword does great damage , Frostner probably does a bit more (Crush > skeleton)
Silver dagger may actually be the best option though (not tested) since it allows faster movement, less stamina drain - and you'll proc Holy damage more often.
2 top tier HP foods and 1 top tier Stamina Food
Use Mead to top up your food bonuses

Ideally you don't want to get hit - so Tasty mead is 100% worth the HP regen trade-off

He has a very brief down time and you need to smack the donkey out of him during that time then run around dodging - repeat

EDIT : Did some research and - Frostner secondary attack is the best thing to use for damage - while spending as little time as possible in Yagluth's face