If you have one device and are just joining the game the absolute best way is to not farm and only grind xp until around level 60. Don't even worry about gear and don't buy any ancient items except maybe a weapon if you are a war ranger or rogue and try to buy that used if you can. Try to form groups, it shouldn't be necessary but mages and druids are harder to level solo.What about using no lux or gold or just the gold u get farming as a low lvl? He wouldn't be able to buy anything with farming at such a low lvl.
If you are a warrior, ranger, rogue buy as many health sigil boxes as you can along the way and a few energy. If you are a druid or mage buy as many energy as you can and a few health (yes even on druid imo).
Once you hit level 60 try to save a bit for a USED heroic ammy, you will probably afford by level 80-90. Used you can resel same price and not lose gold. Buy a flint shop weapon USED if you are war ranger or rogue. You can get to level 100 with no plat items no real money no problem. You wont really feel the burn until around lvl120ish no xp lixes.