Digital signatures are one of the most important security technologies, ensuring the authenticity, integrity, and non-repudiation of data in digital environments. This paper presents the development of a practical exercise on digital signature encoding and decoding, helping students understand the working principles and practical implementation of digital signatures. The exercise includes the following steps: generating public and private key pairs, digitally signing data using the private key, and verifying the signature using the public key. The exercise utilizes the Python programming language and popular cryptographic libraries to demonstrate the implementation process. The results of the exercise enable learners to master digital signature encoding and decoding techniques and apply them in information security systems.