1. Zahid

    Usually in IITs direct admission after B.Tech is bit tough and time dependent. They will ask you to appear for a written test followed by interview. Imagine if they find a candidate with M.Tech degree who is in line with you for PhD admission the competition would be higher and he will have an advantage.

    You can try few things.
    1. Get a clear understanding of one subject. You should be able to address tough topics in that.
    2. Target a prof and his work in IITM. Read papers from his lab and understand what he is doing. If possible visit him and try to do a project with him.
    3. Apply other IITs as well and have a GATE preparation intact.
    4. Try Jan admission as GATE top qualified competition is less during that time.

    Hope this is helpful.

    Good luck with phd admissions.