I'm so used to drawing lykars about 50 times the size of a troll so I thought I'd talk about how big they'd be compared to us.

Length-wise, they can grow around 6ft long (slightly smaller than a bottlenose dolphin)
Height-wise, it can depend on their gender, age and growth, but most likely the height of a large dog (e.g. a Labrador or a collie)