Once you activated then go to site action-->site settings-->Master Pages from look and feel section. Select yoru master page from DDL and say ok.
If you are using foundation, then open your subsite in designer and add your master page in that subsite. Then set that custom master page as default master page by right click on master page. Do it for other subsite as well.
Hope it could help
Hemendra:Yesterday is just a memory,Tomorrow we may never see
Please remember to mark the replies as answers if they help and unmark them if they provide no help.
Marked as answer byAli HyderTuesday, July 30, 2013 8:21 AM
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