I actually wrote two papers on my work, and I want to publish both in same conference. I have now submitted first paper and it is yet to be selected and my second paper is extension of my first paper. I want to publish the second one also. So can anyone please tell me how to cite my first paper? Both are IEEE papers.
One solution would be to post one or both papers to the arXiv, and then cite the arXiv versions.
IEEE does allow posting to the arXiv with certain terms. From their FAQ:
Can an author post his manuscript on a preprint server such as ArXiv?
Yes. The IEEE recognizes that many authors share their unpublished manuscripts on public sites. Once manuscripts have been accepted for publication by IEEE, an author is required to post an IEEE copyright notice on his preprint. Upon publication, the author must replace the preprint with either 1) the full citation to the IEEE work with Digital Object Identifiers (DOI) or a link to the paper’s abstract in IEEE Xplore, or 2) the accepted version only (not the IEEE-published version), including the IEEE copyright notice and full citation, with a link to the final, published paper in IEEE Xplore.
Dual submission of related works is a fairly common occurrence, and need not be problematic. The key question is the degree to which one work depends on the other.
Typically, if you have two pieces that are being submitted in parallel, they should be exploring different aspects of the work. In this case, you simply cite the other paper with its publication date and venue as "submitted." When this is done with journals, one often submits the other paper as supplementary information, but many conferences to not allow this.
If one piece builds incrementally on the other, however (as it sounds like is the case for you), then you should seriously consider whether it is actually appropriate to have two separate papers, or whether they should be combined into one. Otherwise, you may be viewed as engaging in salami slicing, which is definitely a bad thing.