Silicon is the central atom, so we can draw a preliminary skeletal structure:
There are 4 + 4×7 = 32 electrons, and 8 have been used to make four bonds. The remaining 24 go on the two chlorines as lone pairs:
The central atom has four atoms and no lone pair, therefore, both the electron and molecular geometries are tetrahedral:
Steric number 4 corresponds to sp3-hybridization where the idealized bond angles are 109.5o.