How to apply strain on a two-dimensional sheet using VASP?

[surinder]

Hi everyone,
Greetings of the Day!
I want to apply uniaxial-strain to a two-dimensional sheet. I read about it on past queries. I know that I need to make changes in the lattice constants in POSCAR file. But I am following queries:

1. Suppose I have a lattice constants for MoSSe 4x4x1 sheet :
Mo Se S
1.0
12.9938564301 0.0000000000 0.0000000000
-6.4969282150 11.2530097616 0.0000000000
0.0000000000 0.0000000000 15.0385713577
Cartesian
Mo16 S16 S16
------------------------------------------
-----------------------------------------

To put strain in x-axis, I need to make changes in the x-vectors. Right?

Is this the only change required in the POSCAR or something else also need to be incorporated?

2. For the relaxation,
in INCAR what flags are needed than the normal relaxation?


Suggestions to improve my knowledge will be highly appreciated.

Thanks in advance
Surinder