From my point of view, I dont think tones that important for foreign chinese leraners. We have many dialects and the difference between them is the tones. We can understand each other well even though we dont speak standard mandarin. There's no way for foreigners to learn the tones unless you learn all the of them by heart. I mean, of course it will be great if you pronounce tones correctly, but it really dosent matter if you cant. So dont bother too much about it.

feel it. e.g. 火(fire) is 3rd-tone, imagine that you are burning, so hot, unbearable. the 3rd tones often make a serious feeling. 光(light) is 1st-tone which often make one gentle. gentleman is 先生 two 1st-tone words. there is no specific rule, all by yourself.

The tones are as follows: 1st tone. High. 2nd tone. Rising. 3rd tone. Falling and then rising again. 4th tone. Falling tone. (In English when you "shout": Yes!) 5th tone. Neutral tone. http://www.wku.edu/~shizhen.gao/Chinese101/pinyin/tones.htm

Perhaps there's not the easiest way to learn a language, 'the easiest way' is differ from person to person. Insist on listening and reading and then find out your own way :)