The path from Herald to Guardian can appear treacherous but is not nearly as dark as it seems. At the Herald level there are a lot of very basic mistakes and concepts being missed and by simply focusing on the general mechanical skills like last hitting and spell casting can drastically improve your gameplay. To climb from Herald to Guardian we recommend watching the following videos and just generally logging some more hours in Dota to move up quickly.
Focus on general mechanics and concepts that all advanced players have mastered
Learn the game states and hero roles
Introduce basic, well-rounded heroes that make learning easy
Chessie returns to make you wiser once again. This is the guide to watch if you want to see how a professional Dota 2 player binds their keys for heroes and courier. Chessie also explains his other settings and why he uses them.
The laning stage of the game generally lasts for the first 10 or so minutes. This is when players who last hit well can begin building an advantage through their mechanics. This guide focuses on consistently collecting high last hit numbers in the laning stage.