The most common practice right now is to use Bluestacks, root it, use FakeGPS (the app) through Lucky Patcher. This is QUITE the pain in the ass, and many people are reporting issues with Bluestacks closing the game, freezing, logging them out of their Google Accounts.
The Nox App Player (basically the EXACT same thing as Bluestacks except on steroids) has a built in GPS spoofer that lets you walk with the W/A/S/D keys and there's no google account issues.
Here's how to do it:
Nox uses your GPU in your PC to process images unlike Bluestacks. So long as you have something above a GTX 250 you should be fine. : https://puu.sh/q3l74/1e7a8c430c.png
Here's a video guide if you're still having trouble getting Nox installed:
Used to auto walk across your town or wherever to hatch eggs, and loot pokestops (if you're watching it):
Follow this video to get scripts to work:
You can use FakeGPS if you don't like Nox's GPS spoofer (which is quite crude, recommend you use FakeGPS to move from place to place over WASD or Nox's crude GPS Spoofer). Just follow the following directions:
YOU NEED TO HAVE DONE ALL OF THE INSTRUCTIONS FROM THE VIDEO ABOVE FOR THIS APPLICATION TO WORK IN NOX!
Once you've done this, you're good to open the FakeGPS App , set your desired location, THEN open Pokemon Go and play. If you don't care about using WSAD for movement and want to just use FakeGPS, I still highly recommend you do it in Nox. It's much more stable, no errors, better performance, more options. Nox's WASD Movement and built in GPS Spoofer is prone to crashing a lot and will crash Nox. If at all possible use FakeGPS.
If you warp more than 5 miles away from where the game last thinks' you were you WILL be soft banned. Soft ban is that no pokestops work and pokemon are not catchable as they instantly run. These's bans can last anywhere from 5 minuets to 12 hours.
YES YOU CAN go from say New York City to Sydney Australia to hit pokestops and catch pokemon. You just need to wait out your soft ban.
Throwing pokeballs on the PC is QUITE glitchy. You'll miss alot. I highly recommend stocking up before you go hunting, and practice on weak ass pokemnon. You don't want to run into something rare and fuck up.
Sydney, Australia : -33.859048, 151.213183 (4 Stops)
Pokemons Found: Goldeen, Psyduck, Shelder, Staryu, Krabby, Slowpoke, Poliwag
Regimental Rd: -33.88595500, 151.18409300
Science Rd: -33.88593500, 151.18601200
Central Park, New York :40.764871, -73.972722 (4 Stops)
Myrtle Beach : 33.714451, -78.877194 (4 Stops)
Long Beach California good spot: 33.760757, -118.19507