I was wondering what if the best way to bring up smithing (lvl 64) (and mining (lvl 75))? I have tried mining coal/iron to make steel pl8 but that was pretty slow, I tried iron pl8s but i fail to refine the ore more than 50% of the time (200bars/500 ore :|). So are there any better ways or should i stick with iron pl8s which seem a bit faster. (im also mining the ores to bring up my mining so buying ore is out of the question)

Try mining mith and coal? There aren't really fast ways to do it fast without buying ores, and certainly not in F2P.

i would do mith but im probably would want to wait till lvl 68 so i can make pl8s

The best way I've found is to powermine up to 85 mining, mine a bunch of rune for cash, then spend the cash on iron bars and make into plates. I dunno if it's the best way but it works for me.