The following processional and recessional cannot be applied to every wedding.  They are general guidelines to a full wedding.  There are many weddings with a bridal party having fewer members, however, the following rules can apply to those as well.

There should be a short hesitation of time for each group and for the music selection to change for that group.  But DO NOT wait for the music to change as being the decisive moment to proceed, it may have been planned for the following group to enter to the same music.
a)      As soon as the men see that the parents are seated, they should proceed, not before nor wait to cause a longer hesitation.  
b)      As soon as the ladies of the bridal party see that the men are in a standing position at the point of ceremony, they should proceed, not
before nor wait to cause a longer hesitation.  
c)      As soon as ring bearer and flower girl see that the ladies of the bridal party are in position at the point of ceremony, they should proceed spaced apart about 25 feet, ring bearer first, then flower girl.
d)     As soon as the bride and her father see that the flower girl is in position at the point of ceremony they should proceed to their destination. 

When the bride and her father arrive the bride's father should state who gives her away, such as "Her mother and I do", then kiss his daughter, takes her hand to extend it to the groom and give the groom "a stern warning" or other heart felt advice.

Processional

1.) Seating of the mothers:

If grandmothers will be part of the processional, always keep in mind that grandparents of the groom are always the first ones in and the last ones out in the processional.  Easy to remember tip.  If no grandparents then parents of the groom are the first ones in for the processional and the last ones out for the recessional.  

Mother of the groom is escorted to the front row and is seated at the first seat on the right. Father follows right behind the mother being escorted and sits next to the groom's mother.

Mother of the bride is escorted to the front row and is seated at the first seat on the left. If the Father of the Bride will not be giving his daughter away he follows right behind the mother being escorted and sits next to the bride's mother.

2.) Traditional entrance of the men in the Bridal Party:

Single file entrance in this order:   Minister, Groom, Best Man, and the other men of the bridal party, Ushers or Groomsmen. All proceed to the ceremony location lining up to the right.

Traditional entrance of the ladies, ring bearer, and flower girl of the bridal party:

Single file entrance spaced apart about 25' in this order:   Bride’s Maids, Maid or Matron of honor, Ring Bearer, Flower girl or girls.  Bride’s maids proceed to the ceremony location and line up starting to the outside and in the order in which they will pair up with groomsmen for the recessional after the ceremony.  It is customary for the flower girl to toss rose petals (representing the love of the occasion) and that no one is to step on the rose petals until the Bride has been escorted to the ceremony location.

2b.)alternate) Entrance of the Bridal Party:

Minister and Groom proceed to the ceremony location.  Bridal Party enters in pairs spaced approximately 30' apart, separating and lining up from the outside toward the center, men to the right, ladies to the left, when reaching the ceremony location in this order:   Bride’s Maids and Groomsmen, Maid of Honor and Best Man, Ring Bearer and Flower Girl. It is a custom for the flower girl to toss rose petals (representing the love of the occasion) and that no one is to step on the rose petals until the Bride has been escorted to the ceremony location.

3.) Bride’s entrance:

Bride and Escort do not proceed until the entire bridal party is in position and the selected song of for her entrance starts playing. Her Escort is on her left side. If her Escort is her Father, when he is asked "Who gives this woman to this man?" he can say "I do", "her mother and I do" or "her family and I do"  then lift her veil, kiss her on the cheek, take her hand and extend it to the groom, then be seated next to the Mother of the Bride.

4.) Recessional after the ceremony:

Recessional exit is spaced apart to the distance of their photographer, approximately 25' so that each pair can be properly and individually photographed. Pairs proceed in this order: Bride and Groom; Ring Bearer and Flower Girl; Maid of Honor and Best Man; Bride’s Maids and Groomsmen; Mother and Father of the Bride; Mother and Father of the Groom; Grandparents.