Namaste!

1. The main to develop Tejas is thru chanting of Mantras. Mantras
awaken the Kundalni(the pure form of Tejas), who is a form of
Mantras(Kali wears the garland of skulls, which represents the 50
alphabets of the Sanskrit language). Mantras like Om, Gayati can be
chanted. Another way is to just chant the letters of the Sanskrit
language while concentrating on the chakras(each Chakra has some
alphabets). Mantras of fierce fiery Gods like Durga, Skanda, Agni are
also good.

These should be 1st chanted loudly, then slowly whispered, then
chanted mentally.

2. Silence is another way to increase Tejas. While Mantras directly
increase it, silence stops its wastage. Especially gossiping,
unecessary chatting, discussing politics etc should be avoided.

This silence has to be not just physical, but mental as well.

3. Concentration on objects, escpecially a ghee lamp when done as
Tratak, is a very poweful way to increase Tejas. When concentrating,
the mind becomes silent, which allows the inner light to come forward.

4. Gyan Yoga increases Tejas. Constantly analysing " Who am I " , trying
to track the awareness back to the heart. Note this is different from
doing everything mindfully, as that increases Pran. To increases
Tejas we have to be more active, & constantly use our Buddhi(wisdom) &
Vivek(discrimination) to analyse the world, & see the hidden hand of
God in it.

love
Shantnu