Re: Need Tips to Get Better at Dota 2
If we're talking about which heroes to learn, you can usually work with 3-4 well familiarized heroes just fine. It depends on the niches they fill. You want to be as flexible as possible during drafting, having hero-options for gankers, pushers, supports, carrys and the like.
Personal player skill you get simply by playing the game. Experience is a strong weapon. Having prediction skills and good reflexes makes you a ton better on your own already, though personal skill still loses to good teamwork.
Knowledge about what to build/do when you get through guides, experience, pro games and trying to analyze your mistakes in replays. Analyzing yourself is important in many different ways, as no mistakes teach you like your own one.
As a last tip: If you're being annoyed by getting beaten to pulp by a certain hero, you may want to read more about it, what counters it in theory, what its weaknesses are, and possibly even playing the character for a match or two yourself to see what gimps it the most. Knowing every hero's general weakspot is a safe way to allow yourself to be crazy-prepared for just about any situation. If all else fails, you may want to try another hero against the nemesis in question.