To rent an apartment, you need to follow several important steps:

1. Complete a rental application with personal information, proof of income, and sometimes references.
2. Pay an application fee that covers credit and background checks performed by the landlord.
3. Provide rental references or personal references if you don’t have rental history.
4. Pay a security deposit, typically 1 to 3 months rent, before moving in.
5. Sign a lease agreement after reviewing the terms carefully.
6. Finally, move into the apartment once the lease is signed and keys are handed over.

Additional tips include having all required documents ready, responding quickly to landlords, and documenting the apartment's condition when moving in to avoid disputes later.

If renting in Germany specifically, a credit report (Schufa), proof of income, passport, and rental references are typically needed. Also, registering your address at the local registration office shortly after moving in is required.

This process streamlines the search and application to legally and securely rent an apartment.