How can I get to Arcade in the early morning at 5:30 - 6 am? is it possible for the normal price?

It would depend on where you are starting from, if you are in the old city area, the song teaw are running at that hour, and you can expect 40-60 baht. If you can get to the Keaw Narawat bridge or road, 20-40B.. Stating your destination in Thai will help keep the price down.

Nimman, Maya or Kad Huyw Kaew.

there are so shit in the morning at arcade , 100 150b to go somewhere to the city in the early morning

If you have a motorbike or a bicycle you can take yourself to arcade and use one of parking services for 5 or 10 baht a day if that works for you.