Narmada shivaling is for every common man. Shiva lingas are like
fire, Lord Shiva keeps doing penance - jwaalaagni - the fire of
penance blazing all over him & from him - so, we always keep him
cool - he is also called Abhisheka Priya - bathing divine elements
is called Abhisheka in sanskrit. The more you bathe him, the more
happy he is.
Lingam Pooja is done daily with abhishekas (Divine Bathing) with
fresh milk, Fresh Curd, aromatic herbal powders & water chanting the
following mantra :
THATH PURUSHAAYA VITHMAHAE
MAHADEVAYA DHEEMAHI
THANNO RUDRA PRACHODHAYAATH
Light incence and offer dhoop. After bathing the linga, wipe them
gently with a designated cloth - apply some sandal powder moistened
with little water to bring it to a paste form & vermillon. Rudram
chanting pleases Lord Shiva which is either recited or played during
the abhisheka (Divine Bathing).
The above process is the Puja and if done with a pure heart &
consciousness & true aspiration, the Lord will certainly accept it.