Thank you notes
Thank you notes should be sent within ten days of your shower, and within two weeks after you return from your honeymoon.  Wedding gifts sent in advance and received before your wedding should be responded to right away.

DO send thank you notes for all gifts received.  You may also choose to send thank you notes to guests at your wedding.
DON’T send a pre-printed thank you note.  It makes the recipient feel like they were just another gift to you.  A personalized, handwritten note lets the guest know how much you appreciate their gift, and appears more sincere.
DO send separate thank you notes for each gift received.  If you receive a gift from someone at your shower, and then again at your wedding,  that guest should receive two thank you notes from you.
DON’T write in colored ink when writing your thank you notes.  It is appropriate to write in black or dark blue ink.
DO send thank you notes to all friends and family who arranged showers or parties for you.  You should thank them for the party or shower in the same card thanking them for their gift.  

Wedding Party
Traditional duties of the maid of honor include helping the bride select her wedding dress, help address invitations and place cards, organizes the Bachelorette party for the bride, hold the grooms wedding ring, help with the bride’s gown, pay for own dress and accessories, may host a shower, attend rehearsal and rehearsal dinner, make sure bridesmaids, flower girl, and ring bearer are at the ceremony on time, arrange the bride’s veil and train, witness the signing of the marriage certificate, holds the bride’s bouquet during the ceremony, helps the bride change into going away clothes, takes care of bride’s gown and accessories after the reception.

Traditional duties of the bridesmaids include helping the bride and maid of honor, assists the bride with errands, attends the rehearsal and rehearsal dinner, helps gather guests for first dance, cake cutting, and bouquet toss, may make a toasting speech, pays for own dress and accessories, may help with a shower.

Traditional duties of the best man include attending the rehearsal and rehearsal dinner, organizes Bachelor party for the groom, make sure the groom and gets to the ceremony on time, delivers any payments, holds the bride’s ring during the ceremony, makes sure all ushers and groomsmen are dressed and on time, witnesses the signing on the marriage certificate, offer first toast to bride and groom during the reception, takes care of the groom’s clothing after the reception, has the car ready for the bride and groom to leave, pays for own wedding clothing and accessories.

Traditional duties of the groomsmen include attending the rehearsal and rehearsal dinner, participates in Bachelor party, if applicable, make sure corsages or boutineers are delivered to the correct people before the wedding, pays for own wedding clothing and accessories.

Who pays for what?
Keep in mind, these are traditions from the past, and over the years these customs have changed.  These days, more and more couples are handling their own wedding expenses or switching up what family pays for what. There are also numerous exceptions and options depending on religion, ethnicity, or other custom.

Traditionally, the bride pays for the grooms wedding ring, a wedding gift for the groom, own hair, makeup, spa treatment, etc., and gifts for her attendants.

The groom traditionally pays for the marriage license, the bride’s engagement and wedding ring, bride’s bouquet, gifts for his attendants, the honeymoon, corsages for mothers and grandmothers, boutonnieres for the men in the wedding party, officiant fee.

The bride’s family traditionally pays for reception costs- food, music, décor, etc., ceremony décor, flowers for ceremony and reception, invitations, programs, announcements, wedding favors bride’s wedding dress and accessories, photography, transportation.

The groom’s family traditionally pays for the rehearsal dinner- food, decorations, invitations, entertainment, etc., a wedding gift.