Make sure you have read the legal bit on my home page.
In English, an intransitive verb is one with no direct object. You do know what a direct object is, don't you?
In Japanese, the term is "self-verb" - the subject is also the direct object. It amounts to the same thing.
saburinasanhaodorimashita. "Sabrina danced." There is no direct object - Sabrina didn't dance anyone else, she danced herself.
The trick here is getting the indirect object particles right.
TIME: Absolute times are followed by ni. Relative times are not followed by any particle. For durations, the start time is followed by kara and the end time by made.
MANNER: Means and methods are followed by de.
PLACE: A place where something is happening (usually "at" in English) is followed by de. A place where nothing is happening (often "to" in English, e.g. a destination) is followed by ni. In principle, directions are followed by he (pronounced e), meaning "towards", but ni will almost always do instead.
OTHER: If in doubt, use ni.
saburinasanhashyokudoudeodorimashita. "Sabrina danced in the dining room." The dining room is a place where something is happening, so use de.
Present/future tense and negatives are straightforward.
For verbs, use the pre-masu stem.
mahoutsukaisamahatatarisoudesu. "The wizard seems to be casting a spell."
saburinasanhanugisoudesu. "Sabrina seems to be undressing."
For many, many more transitive verbs, see the Can of Worms, a list of transitive and intransitive verbs in Japanese.