Application processes for assistantships vary by program. Most programs that provide Teaching or Research Assistantships will solicit applications for assistantships along with applications for admission. There is no central campus-wide system for applying for assistantships.
Some units will need to hire additional Teaching or Project Assistants from the ranks of their current students, sometimes during an academic year. These processes also vary and are determined by individual hiring departments or other units. Students interested in such positions should contact the hiring department or other unit in advance of any announced positions, to learn about the process and make their interest known. These positions often arise and must be filled on short notice, so are not always advertised widely.