boil your rice rapidly in salted water until it's about halfway cooked (shouldn't take very long), then rinse in cold water and drain.
put a few spoonfuls of oil in a non-stick pan that has a good fitting lid. mix the rice and greens in whatever way is easiest for you (if you made a lot of rice then it's easier to do in sections...) and put into the pot, then take a few sprigs of saffron and crush between your fingers and sprinkle over (saffron used to be worth its weight in gold before gold shot up in price just recently, use sparingly and have dry hands...). if the rice isn't flat at the top that's usually better, shape it into kind of a dome then take the end of a wooden spoon and poke three holes through the rice to the bottom of the pot (for the steam to come through).
pour just a tiny bit of water (two tablespoons maybe? the rice will still have some water from rinsing) and what might seem like a ridiculous amount of oil overtop of the rice (depends how dry you like the rice, but double what you put in the bottom).
put some paper towel between the lid and the pot to make a really tight seal (and this will soak up the steam too). try not to open the pot from here on, cook for five minutes at 2/3 heat to get the steam going then lower the heat to about 1/3 and continue cooking for twenty or so minutes.
at this point the rice will be all cooked and delicious, but you have the option of reducing the heat a little more (1/4 ish...) and letting it cook really slow for as long as you can wait in order to get this really tasty crunchy rice crust at the bottom of your pot. if you do this right you can even flip the rice over onto a serving dish and have what kind of looks like a rice pie.