Once you have the mRNA, it is translated by a ribosome into an amino acid sequence.
The steps that occur are:
1. Initiation: the ribosome assembles around the target mRNA (there are ribosomal binding sites on the mRNA which is where this happens) and the first tRNA is attached at the start codon (almost always this is f-Met).
2. Elongation - The tRNA transfers and amino acid to the tRNA corresponding to the next amino acid. The ribosome then moves (we call this translocation) to the next codon to continue the process. This creates an amino acid chain.
3. Termination - when the stop codon is reached (e.g. UGA) the ribosome gets released from the mRNA.