Things you should know when starting your ritual:
When are you going to hold it: new moon, full moon, waxing, or waning?
What time of the year/sabbat is it: is it going to be a Beltane, springtime, fertiliy rite or a Samhain, autumn, end of cycle kinda thing? If you want to start something new or attract something you want to do it between the new and full moon while the moon is waxing or growing bigger. If you want to banish or get rid of something you'll want to do it while the moon is between full and new; on the backside while it's shrinking or waning.
Why are you doing the ritual: Are you/someone you know sick, do you want a new job, more money, lose a bad habit? If you're looking to gain something, like the new job or more money, you'll want to be doing it during the waxing moon. If you want to lose something you'd plan it for the waning moon. Something like an illness can be done at either time, it just depends on how you word it.
Where are you doing the ritual: inside your room with your cat and a candle, outside with a fire and 5 other people? Though I wish it weren't so, most of us don't get the chance to work with 5 other people (I STRONGLY recomend it if you ever get the chance). You don't want to put a chant that involves stomping around if you live in an apartment building.
What tools will you need: candles, incense, athame? Most of us work on a very tiny buget, no you aren't the only one, so don't feel bad if all you have is a white candle and a stick of cheap sandalwood incense. Once you've figured out all of the above you will want to write it down, you may want to do this ritual again in the future.
Of course, last but not least, you'll want some writen words. Some say that rhyme is the most powerful, others say it's a bunch of bull, I say, whatever you like. If you can rhyme your spells I say more power to you! If not, join the rest of us uncreative folks. I don't think it'l matter either way, she'll listen and if she thinks it's right, it'll happen.
There is always a new Sabbat right around the corner, maybe you could all write a ritual for it. Do a little homework, study up on it and see what you can do. I bet you'll surprise yourself!