Do not use margarine. Unsalted better than salted. May be diluted with olive oil. I don't happen to like home-made. More important than you think.
Heavy bottom is helpful.
So as to not break up rice. These recipes are based on Italian custom together with hard-earned experience. Once you get the knack, you can try variations, with vegetables and so on. Artichoke Risotto is a traditional dish, but my one attempt failed miserably, and i had to spit out the unchewable leaves like tobacco. Not as good as good but almost.