18.1  One should receive the sacred ash (Vibhuthi) only from the Sivachariar.It is equivalent to receiving from Lord Shiva himself.  Receiving it from others or taking it by himself are sinful acts.
18.2  Inside a Shiva temple the Sivachariyar alone is the Guru. For him his guru is the protector. For all God is Guru. HE is the witness for all the happenings.
18.3  Where ever one does pooja ,in whatever manner it is important to remember the guru who taught us the methods of pooja. For pooja Guru’s feet is important. For manthra Guru’s words, for meditation Guru’s form, for moksha Guru’s compassion.
18.4  So by uttering the following words one should start the pooja

OM. Gueu Brahma, Guru Vishnu, Guru devo Maheswara
Guru satchath para brahma thasmai shri gurave namah
Guruve sarva lokaanaam bishaje bava rohinaam
Nithaye sarva vithyaanaam shri Dakshinamoorthaye namah
Sadashiva samarambam sankarachaarya mathyamaam
Asmath aacharya-baryanthaam vande guru parambaraam
Guru saranara vindapyaam namo namah.