It can largely depend on what occult tradition you practice. For instance, if you practice wicca, from my understanding you can cast a circle with sea salt or smudge your ritual space with some white sage before you begin. I personally practice hoodoo, so while I actually do employ the wiccan techniques above, I also try to make use of protection oils that I anoint myself as well as my home with. I also might light a white candle anointed with protection oil and some herbs like Angelica root for uncrossing purposes. Oh yes, speaking of that, I would definitely suggest doing an uncrossing or road opening ritual before beginning. It can be as simple as lighting a white candle rubbed with the respective oil.
Make sure that after protecting yourself before the ritual, you do proper cleansing work afterward. I don't know what wiccans do, but when I do cleansing work, I take hyssop baths and recite the 51st psalm. I then save some of the bath water and toss it over my left shoulder at a crossroads. But that's hoodoo tradition, and you may not be a part of that.