How to make APPLE SALADA with CHEESE and NUTS!

I will prepare a super fresh salad, which is so good!
INGREDIENTS
2 apples (which are half a kilo approximately)
50 g arugula
half a lemon
200 g emmental cheese
a handful of walnuts
For the dressing:
40 g virgin olive oil
5 g vinegar
one tablespoon oregano
and a pinch of salt.