To get rid of any unwanted manifestations, from evil spirits you might have summoned to unsavoury emotional states.
There are many, many banishing rituals, some complex, some very simple. A banishing should be performed before and after every ritual, unless of course you want whatever might be lurking/has been summoned to stay.
Banish with Laughter
Laugh. Although forced at first, and a little bit weird, eventually you’ll be able to laugh on command in a genuine fashion.
Burn some sage and waft it around, asking your ancestors and spirit helpers to aid you in cleansing yourself and the place, and removing any evil spirits.
Of course, you can always make one up. Simply drawing a pentagram in the air at the cardinal points works just fine, although this is incredibly unimaginative.