How to create custom themes in magento ?

Z:\p\app\design\frontend\base\default --- copy all
Z:\angelsincrib\app\design\frontend\default\angelsincrib --- paste to here
Z:\angelsincrib\skin\frontend\default\ create folder ---- angelsincrib
Z:\angelsincrib\skin\frontend\base\default --- copy all
Z:\angelsincrib\skin\frontend\default\angelsincrib ----- paste to all
Z:\angelsincrib\skin\frontend\default\default ---- copy all
Z:\angelsincrib\skin\frontend\default\angelsincrib --- paste to here and overwrite all
Goto admin System->configuration->leftside Design -> themes (translations->angelsincrib, Templates->angelsincrib, Skin (Images / CSS) ->angelsincrib,Layout->angelsincrib)
Now System -> Cache management -> Select All -> Actions=disable->Submit
Now System -> Index Management -> Select All -> Actions=Reindex Data->Submit