Rubuta ci gaba don wannan sakin layi - A shekara ta 1934, ya shiga makarantar Warsaw Academy of Fine Arts kuma ya kammala karatu a 1939. A lokacin Yaƙin Duniya na II da kuma mamayar Poland da 'yan Nazi suka yi
, Tomaszewski ya sami abin rayuwa ta hanyar zane-zane, zane-zane, da zane-zanen katako wanda daga baya aka lalata a lokacin tashin hankali na Warsaw. A cikin 1947, ya fara ƙirƙirar fastoci don kamfanin rarraba fina-finai na jihar Central Wynajmu Filmow tare da abokan zane Tadeusz Trepkowski da Tadeusz Gronowski. Karancin kayayyaki bayan yaƙin ya sa Tomaszewski ya sake yin fim ɗin fim kuma ya gabatar da launuka masu launi, siffofi masu ban sha'awa, da kuma fasahohin yin fim don isar da yanayin fim ɗin maimakon dogaro da hotunan taurarin fim ɗin. Ya kuma kirkiro fastoci don wasan circus da nune-nunen zane-zane, da sauransu. Zane-zanensa na zane-zane sun kasance masu rai da basira, wanda ya sa ya zama "uba" na Makarantar Poster ta Poland a zamanin bayan yakin da ke tasiri ga masu zane-zane na duniya. Ayyukansa kuma sun kasance wani ɓangare na taron zane-zane a gasar zane-zane a Wasannin Olympics na 1948.