Go to Ranhorn. Go the the "Oak Inn" on the flying whale.
Go through tutorial.
Look at tasks in the top left to see what you can do for free currency.
Place up to 15 of your best ascended tier heroes in your Oak Inn. Make sure the 10 you are adding to wishlist are here. You build up until it prevents you from continuing.
B2 is another building. Allows you to hold more heroes. Start opening it ASAP.
Wishlist the 10 desired heroes who have furniture you want.
Create furniture with the currency you get and wallow in sadness at the lack of mythic furniture you obtain.
Buy Oak Inn currency with coins every day. Not gems. The gems cost too much to be worth it. Complete every task you can to obtain as much free currency you can.
Create more furniture and continue to wallow in sadness at the lack of mythic furniture you get.
You aren't getting very far day 1. This is a very long grind. Just do what you can and enjoy it :)
Edit: You can strengthen mythic furniture to even further your stat increases. It costs more mythic furniture.
Found on r/AFKArena here.