I wear a bodhi seed wristlet every day. I only take it off when I go to bed or do something that might get it wet. I got it at a local temple where I had it bound to me and blessed. Wearing one as cheap jewelry that was bought on a whim from a random trinket kiosk, without understanding the significance of its purpose and meaning, is irreverent and disrespectful... or at least plain not nice.
There are a specific number of beads. Mine has 18 beads and one guru bead because I have a small wrist. You can also have 21 beads plus a guru bead for wristlets. These numbers correspond to the number of lines or verses in something, I don't quite know what (it could be the Heart Sutra, but I'm not sure). I don't know how many are on the neck malas... 100+8, I think? Not sure.
It's supposed to serve as protection from evil spirits or any form of evil and accident, but I've found that in all practicality, it protects me from being accosted by overzealous Christians wanting to convert me on the spot or invite me to fellowship meetings. =) Vancouver, Canada is home to a large population of Chinese immigrants who, regardless of the worship they have chosen, usually would not be ignorant of basic Buddhist principles and have the utmost respect for them.
The wristlet is used as a counter. I sit and recite the Guan Yin Sutra once per bead for one full circle. The Guan Yin Sutra is an exerpt of Chapter 25 of the Lotus Sutra. But I'm very unsure of what part.
She is ever longed for, ever sought after, The wondrous voice of Guan Yin,
Listen to the deeds of Guan Yin,
Who wholly responds in every direction;
Her all-embracing vow is deep as the sea,
Inconceivable in its kalpas beyond reckoning.
Serving thousands of millions of Buddhas,
She has intoned the great pure vow.
I will tell you briefly:
Whoever hears her name, whoever sees her
And remembers her unceasingly,
Will extinguish the sorrows of existence.
The spotless pure ray of light,
The Sun of Wisdom dispelling darkness,
Subduer of misfortune of wind and fire
Who illuminates all the world,
The Law of Mercy, and clarifying thunder,
The numinous cloud of compassion
Pouring forth spiritual rain like sweet nectar
To quench the flames of agony.
The Brahmâ-voice, voice of the sweeping tide,
Surpassing the sounds of the world,
Is to be held firm in the mind
Unaccompanied by even the shadow of doubt.
For one who is pure, Guan Yin,
In every pain, suffering and even death,
Can be a centre of reliance.
Perfect in every attainment,
Whose compassionate eye beholds all beings,
A boundless ocean of blessings —
Prostrate, let all revere Guan Yin.
She is ever longed for, ever sought after,
The wondrous voice of Guan Yin,
Guan Yin is the Bodhisattva of Compassion, the Observer of the World's Cries. The Guan Yin is actually a Buddha and has attained the highest level of enlightenment, entitled to enter Heaven, but has refused it so as to stay behind and assist every soul to enlightenment.