How can I be safe and protect myself using trimethyl tin chloride?
In addition to the safety precautions mentioned in the question, the following can increase the safety for the experimentator:


Keep the fume hood as closed as possible with the head outside and the arms inside. Usually this keeps fumes from entering the body, since the fume hood airflow goes the other direction.
Work quickly. While this not only minimizes side reactions of the reactant with the air and other things, it also ensures less exposure time, minimizing vaporization.
As Aesin mentioned in the comment, if you have concerns about the infrastructure, you could always perform the experiment in a glovebox.


In the end, you have to feel confident that the safety measures are effective. If you don't, you will have fear of the reaction, and inevitably be less concentrated and more prone to errors. In combination with "work quickly" this may well become a disaster.

Maintain a healthy portion of respect, keep quenching agents close by and execute the reagent transfer with a steady hand.