For working, and many others things during your daylife, is important to learn portuguese. Your university should have language courses avail- able. If not, you can always reach us, or the international relationship office at your university, and ask for language courses open for erasmus students.
Second thing, you have to deliver a curriculum vitae with every activities and certificates you have, particularly about the area you are keen on practicing.
Third, if you are living in Lisbon and are a EU citizen, you should the headquarters of the “Câmara Municipal de Lisboa” near Entrecampos metro station, and ask for a residence cer- tificate and fiscal number. You should take your ID or passport with you. After that, you are ready to contact all the potential employers.