The right sign for "talk" depends on your meaning.
If you mean "talk" as in "He was talking," then you can use the general sign
for "talk" that uses a "4"-hand and taps the chin twice.
(general sign) (side view) "TALK-(speaking) ("talking")
If you mean "talk" as in "They were talking to each other last night" you
can use the version of "talk" that I refer to as "TALK-with." This
means to have a dialog.
Here is a "side view" of "TALK-with." (Either that it could be or a front view of "I
was talking with him.")
Note: You can initialize this sign with "i" handshapes to mean "interview."
If you mean "talk" as in two or
more people were "chatting" you can sign, "chat."
Sample sentence: Do you like to chat with Deaf people?
There is another way to sign "chat." This other version uses an alternating
up and down movement.
CHAT (version 2)
For some notes regarding the sign
for "chat" see the "chat" page at: CHAT
See: HERMIT-("Talking to yourself")