I got 40-73 fishing in like 3 days (not 24/7) its really fast with bot, just buy 20k feathers and your set.

Either cook the salmon and trout, or sell them raw. If you want more profit, sell raw, even if cooked is more (idk if it is), you will burn some, so ye

if you are member, i recommend hunting, its really good too, or else, 80 fishing fast and make money from that. If your not member, go fish swordfish at 70ish or lobs at 65+ to make money. I heard there is a guy in Karmja that notes all your fish. Also, you can get wc to 70+ from willows (gl finding a non crowded world) and then cut yews. Almost every skills that you keep lvling up will eventually make you profit, unless its like smithing or herblore and summoning. Also, rune crafting is good too, once you can do nature runes (member i think) its really nice. You just need to stick to 1 skill. No point in having 10 skills at 55, I'd rather have 1-3 skills at 70 and make twice more money.
EDIT: I know you're not a member, but I wrote anyway, just in case you ever decided to be once, you wouldn't have to ask same question

. Hope i was helpful (some money making ways are not capable of being done by bot, if you wan't real money, you gotta earn it.)