It would probably be easiest to learn "section by section," like a,i,u,e,o first and then ka,ki,ku,ke,ko... and so on. then after learning all of the characters and sounds individually, learn the combination sounds like kya, nya, ryo, sho, kyu, chu. The combination ones are what I think you are referring to when the characters change (get smaller) when paired with another character. きゃkya、にゃnya、りょryo、しょsho、きゅkyu、ちゅchu。:) Find a good chart with all the characters and combination sound and familiarize yourself with them. Also remember that things like "kyu"きゅ and "kiyu" きゆ are pronounced differently. Notice the "yu" in kiyu is bigger than the "yu" in kyu.

Hi! I'm actually studying Japanese in school and I might be able to help. Katakana is only used for English words or words that are not derived from the basic Japanese language. For example, your name would be written in Katakana. Certain characters can change but that's when you start entering kanji. For example "to go" is いきます。(ikimasu) but when you start getting into kanji it will look like 行きます。 (I hope that's what you're questioning about.) As for memorization, you really just kind of have to do practices everyday even though it might not seem like the most fun thing to do. The more that you kind of force yourself to practice it, the more you'll recognize it and learn it.

Hi! I am studying Japanese too. This website really helped me when I was learning http://www.learn-japanese.info/indexw.html Also it is about repetition. You just have to set aside time every day and practice. When the characters start to change that is getting into grammar, like how it changes with verbs and certain sentences. Just learn both Hiragana and Katakana first then get into the grammar points.

Hey! I don't know if you've found something by now that works for you, but otherwise tofugu is amazing! It offers really easy mnemonics that make the whole process easier. Hope this helps! http://www.tofugu.com/guides/learn-hiragana/ http://www.tofugu.com/guides/learn-katakana/

How about if you use picture story book of Japan ? ^^ and.... https://www.youtube.com/watch?v=Njvulx5N_qE https://www.youtube.com/watch?v=8zfBMDNkJuI