"Tal" - this is a common Gorean greeting. Some Goreans combine it with a gesture. They may raise the right hand to their shoulder level, palm inward to show that the hand is free of any weapons, facing the body. This symbolises that the person being greeted is not regarded as an enemy.
Of course slaves have no permissions to wear weapons, so this greeting gesture wouldn't fit to their behavior. Furthermore slaves have to show respect towards all free persons, they cannot look upon any free person to be their enemy. It even might happen that it will be regarded as an insult towards a free person.
So of course may Slaves use the word "Tal" as a greeting but they would not combine it with the hand gesture. You can find examples in the books where slaves use "Tal" as a phrase to greet.
You may add to the phrase "Tal" the person you would like to adress as "Tal Lady (Name if you know her), Sir (name if you know him), Warrior, Ubar or what ever you know or mean to recognise cuz of the caste colours for example. But be aware Profils don't exist in rp.

Instead of "Tal" some Goreans prefer to use
"Greetings...." in the same manner.
"A Gorean slave, incidentally, always addresses free men as "Master" and all free woman as "Mistress" - Captive of Gor, page 73
Apart from the Etiquette of Greeting it is important to know for a slave how to behave in many respects. These quotes are an example for one part:
"It is common," I said, "for a slave to request permission to speak." - Magicians of Gor, page 193
"May I speak, Master?" asked the girl.
"Yes," I said, as Marcus would not respond to her. This permission may be given by any free person and is effective, unless it is overruled by the true master." - Vagabonds of Gor, page 486
"(I) Wish You Well": This is the common Gorean phrase similar to "farewell". It may be used by free persons or slaves.
"be well..." is also a gorean phrase but Slaves shouldn't address free persons with it cuz a slave shouldn't give the impression to sort of command a free person. But it is quiet often used by free persons towards the slaves - in that way as well..
"be well and serve with fire lilone"And well you may find a lil Gorean desert special:
"well wishes, may your water bags never be empty"These phrases are the common one's - while travelling through Gor you may find many variations. Would be interesting to read them here*smiles