If you don't have premium, you can at least :
1. fire your workers and produce gold
2. Hire siege weapons and leave them at your provinces(your main province is the best for this couse sieges cant be destroyed there )
3. Sell all resources(you can also sell and buy repeatedly to reduce your gold to near ZERO)
If you calculate it good your upkeep from sieges will nullify your income and you will get negative gold so nobody would farm you after you quit the game.
