An important party member and it may not do as much and i will again only keep the basics, there are different bonders
They usually used for smaller party under 6, but when only useing the skill Life Bond and an extra damage reduction skill it's possible to bond up to 8. Offcourse just mix around and put enchantments over the weaker players.

Insperation magic 10
divine favor 10+1+3 (rune and headpiece)
Protection prayers 11 + 3

-Life Barrier(e) or any other Divine Favour/protecting prayers elite depending on the party size and offcourse what you prefer.
-Life Bond
-Blessed signet
-Mantra of inscrïptions
-Balthazar's spirit
-Ether Signet > can be left out
-Hex removal or condition removal. low cost offcourse. most used are: reveiled hex and drain enchantment, because they also give extra energy.
-generic ressurrect

When bonding you put and maintain enchantments on the party so that they get less damage. This takes a while so ask your party to wait until you are rdy to move on. Blood ritual or Blood is Power from a necro can help very much when setting up bonds. Every enchantment you maintain has a upkeep of 1 energy degeneration. So blessed signet is used have enough energy. Allways try to hold up mantra of inscrïptions, else you still will run out of energy. Also ask your party not to rush, else you walk too much and cant use blessed signet enough, and will run out of energy still.  

It can be tricky at first but when you get the hang of it, it's pretty easy. also when bonds get removed you can try to put them back on if you can find on who you kept the bond. but be sure not to put yourself in harms way, because you have two superior runes.