Ck your ehr for jobs open. Then apply for it. Then partner with tl & tell them I want to be a tl. If you are a Stella tm, who is a go getter, with green scores, never calls out & willing to work hard. You will get prep by your tl or etl on how to answer the tl interview questions. There will be a high level of commitment & expectation from your upper management & spot, once you become a tl. Your upper mgt will decide what area you work in. Could be soft lines, food ave, or whatever.
We have several threads on this topic, search under interviews, etc.
Here is one link: http://www.thebreakroom.org/showthread.php/2575
Become more involved with the vibe and guest service. New TL interviews are based more on guest service instead of tasks. Being a backroom tm you probably have minimal interactions with guests, i'd start there. Ask about cross training in electronics,instocks,etc.
If you are offered an interview, make sure you are aware of what is going on in your store. What are the store's strengths & opps? What are you doing to impact these? The transition from TM to TL is quite drastic - showing that you are looking at the bigger picture, not just your backroom tasks, will go far.