Right technique for using Xrite and getting perfect white balance / color?

[Ravikantsharma]

I recently purchased X rite passport color checker and have have some query on how to accurate measure it..
mentioned below is process I follow.

• I set my strobes at suitable power , then I use my light meter to take measurement under model chin and set the strobes as per light meter reading.
• Once I get a perfect exposure, I put grey card side of X-rite passport checker under same light condition and take a picture of grey card …(Do I need to fill the frame or 70% of the frame with the grey card ????). I currently use 50-70 % of frame .
• Then I set my canon camera white balance to use that image as Custom image.
• Under same light then I take a picture of Xrite passport checker with 80% of checker in frame.
• In post-production, as my while balance is already set for all images so I don’t touch image with grey card , however the picture with Xrite color checker with multiple color , I custom pick the color which I want to go for and then applies that to all images using lightroom 4.
• 2[SUP]nd[/SUP] concern was , In lightroom 4 when I choose picture which has my Xrite color checker and then try to create a profile based on same, thought it says operation successful, but it ask me to replace the earlier profile which I had created earlier from a different shoot ?

Please guide me if all my above process are right or somewhere I am going wrong as I am not getting the colors which I am looking for.

rds
Robin Saini