Thomson scattering can serve as a diagnostic tool to analyse plasma parameters, e.g. density, temperature and plasma composition. In this work, Thomson scattering in warm dense matter is presented within a self-consistent many-particle theory. The influence of collisions is investigated and provides an improved description of the experiments in comparison to the commonly used RPA. The dynamic collision frequencies have been calculated using a quantum statistical approach within linear response. Going beyond Born approximation, strong collisions and dynamical screening are taken into account via the Gould-DeWitt scheme. The experimentally accessible scattering cross section is determined mainly by the dynamical structure factor of the electrons. In some parameter regions, the inclusion of collisions modifies the dynamic structure factor significantly. Different techniques to determine the density and temperature are discussed in detail. In particular, the determination of the density via dispersion relations of the dielectric function is analyzed and improvements are suggested. Moreover, in preparation of experiments planned at FLASH, calculations of the scattering cross section using different scattering geometries and laser wavelengths are compared and optimal experimental conditions are proposed.