Testimony of fines after accident

Hello dear community, after my accident, in which I waited so long for the damage regulation, I get today a summons for the witness hearing in the case of the fine against my opponent. Now the situation is regulated by insurance technology. 100% e.g. of the opposing insurance (other vehicle drove at red in my Vectra). Give me now a hint, what I should avoid with a witness statement. Even if no blame falls on me, kan After all, I was in private last in the 1970s in court. Nice greeting Carsten