@Pefferie & Brendan,
I agree with Brendan, mnemonics don't seem to work well past the first handful of characters. You'll find that you spend more time and effort trying to create or follow a mnemonic device system then it would take to just learn the character by rote or spaced repetition methods. I've also found that often times those clever mnemonic devices tend to obscure the meaning in my mind.
I adhere to visualization techniques. Very simple and direct. For new characters I just try visualizing what the character is about. For sentences, phrases etc., I just try and visualize the scene, form a sequence of pictures or a movie in my mind it works well in most cases.
That being said, I did use mnemonic devices in the past and occasionally they worked for me.
EG: the character 累 lei4. When you're tired it makes you want to lei4 down.
Having said this, I suppose it is a matter of different strokes for different folks. For some, mnemonic devices may be a powerful learning tool.
Flashcards don't work well for me either. I've found just reading words in sentence form is the best way. It's stimulating and there's always the anchor of context to remind me of the meaning.
I wish someone would create a series of sentence/phrase flashcards. One's specifically designed to be context-loaded. The target word could be highlighted and surrounded by contextual clues in simpler language. Could be especially great for learning 成语.
As Brendan mentioned, learning by watching movies is excellent. I did that at the beginning as well (until I'd gone through every interesting Chinese movie, I currently own several hundred).
Just like Brendan said, first watch it with the benefit of English subtitles. Try to pick out whichever words you can understand and relate them to the English meaning. The next time around watch it with Chinese subtitles. Again, try to pick out which words you can understand and each viewing things will come together more and more.
The great thing about movies is that there's often a strong visual context to help you grasp it.
I would often stay up until 2:00 or 3:00 AM, just watching, scene by scene, pausing and looking up new language in my dictionary. At the beginning one scene might take an hour to get through, but the feeling of satisfaction after getting through a movie and understanding it (even partially) was so intoxicating.
However, at the beginning try to stay away from historical epics or Wuxia films, 武侠片 because the dialogue is not in modern Chinese. My rule of thumb is, at the beginning stay away from any films with long beards, silk clothing, qipao, emperors or chop-sockey Kung Fu moves. At least for study purposes.
I'd like to say that I adhered to the 胡，丝，旗，拳, 皇 principle of Chinese language learning. If a film included any of those five things then I wouldn't study it.
Studying song lyrics is also very useful.
I just wish there were a Chinese resource for Chinese film scripts like imsdb.com is for English film scripts.
As Brendan said, after you learn the radicals, just start practicing characters. Once you write it 30 times over you won't forget it. As long as you THINK about what you're doing while you write it. If you don't think then it might take hundreds of repetitions to remember it. Break it down into the components, 取 is a 耳 and a 又 and think while you write and it might only take 5 repetitions.
Like Pefferie mentioned, learning a simple book is an instant confidence booster and great for learning the first few hundred characters. It will help build a strong foundation in the basic building blocks of the language, while at the same time giving you a constant sense that learning this complex language IS possible and in fact much easier than you thought.
I once read a blog published by a friend of one of the Popup members who said, "Learning Chinese is a five year lesson in humility. I used to think that meant in those five years you'd be fluent in Chinese and also learn humility along the way. Now, after six years of learning Chinese I now realize that what it actually meant was, that after five years, your Chinese will still by abysmal and you will be thoroughly humiliated."
With the right study plan there's no reason why you can't beat those odds. You can learn Chinese in just a few years and your Chinese will be pretty good, you'll be able to read, to write speak and understand.
Just remember to be smart about how you study and you'll get there.