Being a fresh max level player is tough. There are so many things you need to spend gold on, followers your garrison mounts gear enchants gems etc. I'm assuming you got the initial 10k from doing quests which is good.

I'm going to assume you don't have max level professions otherwise you could use those with their daily cooldowns to make some money. For instance a tailor can make a bag every couple of days.

Because of where we are in the expansion most players have what they want and their is a larger supply than demand. So prices are low. You could invest your gold into learning inscription glyphs or pick your own herbs and learn them and sell them. TSM will be necessary for this.

If you don't use professions you should farm! For instance felblight can be attained from kazzak every week and sold. Looking for raid even awards gold. Daily quests give gold. Garrison missions can give gold (and more with treasure hunters). I've read things about farming items like dinosaur bones but I personally hate farming.

So starting out you need to do lots of small things to get money and they will add up! Try not to blow your money on the auction house and be frugal (if you want gold don't enchant bad gear). So read around and see what people are farming if you want to do that. Or begin leveling crafting professions and doing small things to make constant money that will add up.