When you're learning to write Kanji (but since you're writing Chinese I guess you already know how to write Japanese Kanji...), you should learn the different readings for each. I am not an expert on Kanji pronunciation in Japanese, but there is a different reading for Kanji in a compound, on it's own (sometimes), and also as a verb. Once you learn these you will be able to make an educated guess at what the reading is in context. Try looking up "on" and "kun" readings on the web and see what comes up. After learning Chinese Kanji this may sound painful, but you might have to "go back to basics" and write the furigana for each Kanji on a notepad for each different form, and say the sound out loud. This might help you remember. Try using flashcards to memorise the sounds, too.

Have a Japanese friend or teacher who you can ask in person or over the phone/Skype.