Honestly you should not read guides.
Guides are a handicap to many players because they don't know what an item does or why you're buying it, they just know to "get it because the guide said so".
For example lets say my guide tells me to get a Black King Bar and I have no idea what it does, and I'm playing against a team with no magical damage.
That's just as noob as getting one because you felt like it.
The main thing you need to do starting off is to explore. Explore heros, explore items, explore team composition, lanes, jungles, rivers, ancients, etc.
Many people who have tried to learn DotA get it set in their minds that they can only play one hero because they only pick one hero and only practice one hero because many (sorry Rhi, I'm picking on you :p) of our teachers say "get good at one hero, then you can try others". Mod did this with Crystal Maiden and that was all he played, and he never wanted to play anything else, Rhi used to do this with WindRunner as well. You NEED to try other heros early and ESPECIALLY other roles. If you play a carry your first game, do a support next game. My first game I played Sniper and got wrecked, so I switched tactics and played Windrunner, and did a little better.
That is another thing too, you need to come to terms with the fact that you are probably going to lose (badly) unless you improve yourself. When I lose a game of DotA even now I look back at what went wrong and try to improve upon it (90% of the time we forgot wards, they're more important than you think).
Also, once you learn the basics (as in the extreme basics, like the button that says "shop" is where you buy things) you need to do online games. Bot games do serve a purpose, yes, but at the same time they are not ideal for learning. Bots cheat, and make mistakes that normal players would not make (even newbies) and doing only bot games kills your confidence.
Let's say you win a few bot games and go "I'm ready for online!" then get stomped... Would you really want to do another online game? A lot of our players are like this, because to play an online game is out of their comfort zone. A large part of learning to play (and be good) at DotA is getting comfortable with what your doing and whats going on, and if you're only comfortable when you play against the AI, that's being uncomfortable with more than half the game.
When I started playing DotA there was no bot mode, you could only play online, and many new players got wrecked, often. The reason why they added bots (originally) was so that new players would have an easier time learning the extreme basics and advanced players would be able to try out new builds or strategies against opponents that fight back, without the hassle of an actual DotA game.
Just explain to people that you're new and learning, if they're asses, ignore them (there is actually a mute button in the scoreboardish window). The best thing about online games is that it is the environment you're going to be playing in 90% of the time, and it will make you better by practicing in it.
tl;dr
You need to get comfortable with playing the game, not with a hero, not with a role, with the game, and once you are, and are able to adapt to the situation, then you'll succeed