Step 1: Use lewis structure guidelinesto draw the lewis structure of XeF4.
Step2: Apply VSEPR notation, A X E
A=Number of central atoms
X=Number of surrounding atoms
E= Number of lone pairs on central atom
For the above molecule VSEPR notation will be AX4E2
Step 3: Use VSEPR table to find the shape.
AX4E2 has square planar shape. So the shape of XeF4 is square planar
Download a copy of VSEPR shapes table here