This is essentially the same term as posted by Farah Abidi, but without the trademark ending of "Urdu speaking" Urdu speakers. Urdu speakers come in many varieties.

I would say mine is a more general term. But if the adressee is an "Urdu Speaking" person or from Karachi, you may want to use Farah's term, he might consider it more polite. If the addressee is a "Punjabi" or any other who speaks Urdu, they may prefer my ending...for them the term given by Farah would sound slighty pretentious...but coming from an "Urdu speaking" person it is normal and natural.

Both of the terms I have discussed are polite terms that can be used for eldery or younger people when being respectful. But for close friends who are equals, one would say:

اپنا خیاں رکھو

I would suggest using my target term which is a middle ground, and just asking the adressee what he prefers in the future.

One point that may help IF the addressee has been addressed in Urdu: If the addressee has been addressed by "aap" [polite "you"], use one of the two politer terms. If the addressee has been addressed by "Tum" [informal "you"] use the last term I gave.

My apologizies to all for such a long winding reply to such a simple question, but nuances matter.


--------------------------------------------------
Note added at 5 hrs (2007-04-26 01:18:13 GMT)
--------------------------------------------------

I'm sorry, I just realized my "laam" didn't show correctly:
The source terms should be: اپنا خیال رکھیں
The last informal terms should be: اپنا خیال رکھو