GPM always depends.
On lane you can't get high GPM (that is, 700+) unless you stack camps or get them stacked.
If you solo queue and have solo lane, get quelling blade and start stacking creeps and make sure you cut paths with QB so creeps always have free path to the camps. Instead of static farming (keeping creep equilibrium, harassing hero out of lane etc) you sometimes just have to clear the creepwave ASAP and at the same time pull in the creeps so they transition to the neutral camp right as the enemy creepwave is cleared.
This is heavily dire-dependant but it's a general idea of how it should work, for Radiant you can just stack medium camps and pull them in normally after killing enemy creepwave.
If you play an ancient-killer carry, get HotD and start stacking ancients.
Never forget TPs for proper movement. If you play a carry with high killing potential, go kill heroes whenever you see a good pickoff and don't have to invest too much time into it. Best case scenario, catch out a hero who's pushing lane so you can farm creeps right after.
Of course, if you play Mirana you should more actively look for them than Anti-Mage or Spectre, but you still have to think if you'd win more by killing or more by farming.
Sometimes (or rather, most of the times) farming is better than killing or waiting for a teamfight to break out.
Never tp into losing teamfights where you know you won't be able to win it or have a chance of dying if you have to sacrifice farm for it.
The easiest heroes to practice high GPM-ing are Gyro & Drow Ranger.
Drow with 800+ GPM is really easy to do if you get the gist of her. If I have absolute freefarm on lane, I just buy HotD before any other item and start stacking ancients, with lvl 6 you can already farm them due to ulti. She's got massive damage as well so missing creeps is more seldom than other heroes.
tl;dr
The most important thing to get that high GPM running is having a proper rotation, never tp/walk(which is even worse) somewhere where you can't farm or/and kill.
Also, don't be lazy. Try to stack neutrals whenever you can, if you have Ancient-farmer, buy HotD and stack it up.
Quelling blade also proves as very useful as you can stack multiple camps with it
PS : If you can't get your teamm8s to buy wards, buy them yourself. It's better to lose 150 gold than 300+ & farm time.
PPS : If you have russians in your team, get dagon and shadow blade. Try to steal whatever you can and gtfo jungle farm