Happy-sky Charm
By weaving long grasses, red or yellow flowers picked in sunlight, blue flowers picked in moonlight, and white flowers picked in starlight into a closed loop, a charm is created that is said to improve the wearer’s luck. The charm must be worn continuously for a period to attune it with the wearer’s personal resonance, whether as a bracelet, crown, or other decoration. The acts of creating the charm, of putting it on to begin attunement, and calling upon its powers each require a ritual and invocation. Of course, there are many similar charms from a variety of cultures that will grant a similar luck, but only one will have an effect at a given time.
The base difficulty of creating the charm is d4, and during the attunement the wearer gains a point of strain that cannot be removed. One the charm has been activated, while it is worn it allows the bearer to re-roll one check each day. The benefits last one day for each hour spent attuning to the charm, up to a year and a day.

Whatever works for you, really. Source. Because of course.