Soundarya Lahari Sloka -33

[sowbhagya mantram]
[sakala sowbhagyam]

Smaram yonim lakshmeem tritaya-mida-maadau tava mano
Nidhaayaike nitye niravadhi-mahabhoga-rasikaah
Bhajanti twaam cintaamani-gunanibaddhaaksha-valayaah
Sivaagnau juhvantah surabhigrita-dhaaraahuti-sataih

Smaram - "Kleem" the Kaama beeja mantra
yonim - "Hreem the Buvaneswari beeja mantra"
lakshmeem - "Sreem" the Lakshmi beeja mantra
idam tritayam - these three
aadau - in the beginning
tava - your
mano - of the panchadasaaksaree mantra [ the divine mind ]
Nidhaaya - combining
yeke - few persons
nitye - Oh! eternal! Goddess Supreme!
niravadhi-mahabhoga-rasikaah - knowing the aananda from the continuous unbroken japa
Bhajanti - do the aaraadhana or pooja
twaam - you
cintaamani-gunanibaddha aksha-valayaah - making the continuous stream of thoughts as the japamaala
Sivaagnau - in the agni in the sakti triangle in the Sri Cakra
juhvantah - doing [ offer ]
surabhigrita-dhaaraahuti-sataih - hundreds of aahutis by the aatmaananda obtained by the ghee given by kaamadhenu

Oh! eternal Goddess Supreme! few persons knowing the aananda obtained from the continuous unbroken japa, do the aaraadhana or pooja for you, making the continuous stream of thoughts as the japamaala, in the beginning of Your divine Panca Dasa Aksharee mantra, combining the three "Kleem" [ the Kaama beeja mantra ], "Hreem [ the Buvaneswari beeja mantra ], "Sreem" [the Lakshmi beeja mantra], offer hundreds of aahutis by the ghee given by Kaamadhenu in the Agni in the Sakti triangle in the Sri Cakra.

There is similarity between the Panca-Dasa-Aksharee mantra and Saavitree mantra.
In the Panca-Dasa-Aksharee mantra there are three kootaas whereas in the Savitree mantra, there are three paadaas.

If we add with the Savitree mantra, the three vyaahritees Bhoo, Bhuvah, Suvah, then the mantra gets converted to Gayatri mantra.
So too, in the Panca-Dasa-Aksharee mantra, if you add three of the five vimarsa pranava mantras called aim, hreem, sreem kleem, sowh, then the mantra gets converted to sowbhagya pancadasaaksharee.

In this sloka it is directed to add Sreem-Hreem-Kleem;
there is also another alternative mantra called sowbhagya mantra which is formed by adding aim-kleem-sow in the beginning of each koota.

Sivaagnih :-
In the triangular shaped kunda if you form the agni, it is called sivaagnih. Great devotees, offer pure ghee obtained from cow on this agni with the bhaavanaa "sivoham" and apply all their actions [manasaa, vaacaa, karmanaa] to the god.

Bhavanopanishad says :-
Aham twam asti naasti kartavyam akartavyam
upaasitavyamiti vikalpaanaa-maatmani vilaapanam homah.
Juhwantah – offer to agni the goddess – this is called antar yaaga.
Chintaamani guna nibaddhaakshavalayaa – the japamaalaa has fifty one akshara shape. In that the place for the letter "Khsa" is called "meru". It is the sacred stone in the centre of the japamaalaa. Once you do the japa with the maalaa- counting, you should not cross over the meru, but go in the reverse direction then on reaching the meru. You only touch the meru.
The devotees can do this offering in one of the three ways depending on their mental condition; if he is a beginner [not a spiritual one], then he can do the offering with the materials in the agni physically formed one.

Second case is, he can offer the mentally prepared aahuti in the mentally prepared agni.
The third case is [for a spiritual seeker] , he can offer the aahuti in the agni in his own heart of hearts.

This is referred by Bhagavaan Raman Maharishi thus in his "Upadesa Saaram" thus :-
Kaaya vaag mana kaaryamuttamam
poojanm japa cintanam kramaat

Smaram yonim lakshmeem :-
Smaram represent "ha"kaara
Yonim represent "sa"kaara
Lakshmeem represent "ka"kaara

In the sloka referred in sloka 32, in the mantra,
"ka ye ee la hreem ha sa ka ha la hreem sa ka la hreem"

Replace the first three letters by "ha sa ka", "haadi vidyaa" or "lopaamudraa vidyaa" is formed.
Aksha maalaa – is a prateeka of the sabda brahma which is imperishable which is also appearing as the destructive prapanca.

Antar nirantara nirindhanamedhamaane
Mohaandhakaara paripanthini samvidagnau
Kasmimcidadbhoota mareeci vikaasa bhoomau
Viswam juhomi vasudhaadi sivaavasaanam

In the inner heart of hearts, unbroken, but without indhana, lighting and destroying the mohaandhakaara and for the strange mareecis serve as vikaasa bhoomi – such a samvit shaped agni –
in this agni, I offer everything and anything in the world including Earth and Siva. [this is aatma samarpanam].