How do I play Earth Spirit?

This hero has imo a lovely skillset - an aoe silence, stun, slow, mobility as well as respectable damage over time. But how exactly do I play him? I've seen dotafire guides like TheGooGaming's which tell me to go mid, while I've seen people mentioning that he works as an offlaner too. I have also watched a fair amount of videos with people building carry/ganker items on him, so yeah - how exactly does this hero work (assuming he works in the current meta)?

You should lane wherever you are comfortable. Just don't make him a baby sitter. I have also seen him being played as a roamer and he works pretty well that way too. As for the item builds, it depends upon the role which he is playing.
BTW, if you have never played him in a pub, I'd recommend trying out his skills in a bot match/private lobby works. Especially the stun and the roll.

Even though Earth Spirit is an versatile hero and can fill multiple roles, I prefer to play him as an offlaner, mainly because he can get really easy experience, and that's all this hero really needs. Unless you're playing in some kind of trash tier (sub 4k I'd say) you shouldn't have a easy offlane, but if your enemies are really tryhard then you can just pull a range creep into some trees, blocking him and effectively making enemy creeps push the lane closer to you, thus securing easy experience and maybe even farm. Then it's all about good control from you, like with any other offlaner. Then at level 6 I'm starting to roam really hard around the map and create space for my carry, pretty much all my income comes from ganks. Starting items are tango + salve + clarity + shield + iron branch + ward from supports. Depending on enemy team you either want to block the pull camp (against solo support) or just get vision over the pull camp (against dual support). Then you head back between your t1 and t2 and pull ranged creep into trees to secure ez lane :D. While this hero can play with pretty much any items, my standard build is bottle into brown boots into eul into aghanim's, and then full utility (force, blink, auras, etc.). I think that the most important tip is to position yourself well during mid/late game, so that you can save your team mates with grip AND find good opportunities to initiate with roll/stun. Also - don't waste your stones like a fool.

Profile if you're interested to check my games - http://www.dotabuff.com/players/53605643

Earth Spirit is a hero that requires a lot of practice. It's a hero where you need to know how to get your combo off on people, when to move the enemy around and how to save your teammates.

I feel like mastering a few more easier heroes is how to learn how to play Earth Spirit.

Playing Mirana or Pudge will improve your skill shots so that you can get your Boulder Smash off effectively. I picked Mirana and Pudge as their projectiles are around the speed of the boulder.

Playing any hero with Force Staff will help you with saving your teammates with Boulder Smash as well as when to use your role to run away.

Dazzle will help you when to get your teammate out of trouble which will help you know when to pull your friend out of trouble with Geomagnetic Grip as well as learning what a "subtle" AoE ultimate can accomplish when done well.

I am by no means a fantastic Earth Spirit as I don't play him much, but when I do I'm semi-decent with him as I play the other heroes a lot

I agree with dzikapanda, I think that the best position for him is solo offlane.
Dmg on his pull and kick got nerfed, and you need lvl 9 to have them do 400 dmg.

Just like everyone said, I think his best position is to solo offlane. He's reliable on levels and not so much on items.

I usually play Earth Spirit as a ganker/crowd control/semi-support. He's extremely good at ganking and saving greedy carries not to mention he has a lot of team fight presence.

In easy 4 steps you can..

1) close dota2
2) Lie down
3) Try not to cry
4) cry alot..

:(