[CentOS] Adding a new disk to an existing raid 10

Tue Apr 1 08:21:52 UTC 2014
Roland RoLaNd <r_o_l_a_n_d at hotmail.com>

Dear all,
I'm not used to handling software raid.
I've inherited a server which has raid 10 set.
one of our disks failed, and it's to be replaced today.
My question is; any hint how to add this new disk to the existing raid array ?
first thought is :- Create identical partitions as other disks in the array i'd like to add it to.- add it to raid.
Though i'm extremely worried of messing things up and wiping all my data.
Any hint would be appreciated