Step 1: Access the Class Builder (SE24)

1. Log in to your SAP system.
2. Go to the transaction code SE24.
3. In the “Class/Interface” field, enter a name for your class starting with `Z` or `Y` (e.g., `ZCL_MY_GLOBAL_CLASS`) to indicate that it’s a custom development object.
4. Click Create.

Step 2: Define the Class Attributes

1. In the “Class Builder” screen, you’ll be prompted to enter a short description for your class.
2. Choose a class type. For a typical global class, select ‘Class’.
3. In the “Attributes” tab, define the attributes (variables) that your class will use. These attributes can be public, protected, or private depending on how you want them accessed.

Step 3: Define the Methods

1. Navigate to the Methods tab.
2. Define the methods that your class will use. Methods are the functions that belong to the class and operate on the class’s attributes.
3. For each method, specify whether it’s public, protected, or private.
4. Provide a meaningful description for each method.

Step 4: Implement the Methods

1. Select the method you want to implement and click on **Method** in the toolbar.
2. The system will take you to the ABAP Editor where you can write the code for the method.
3. Implement the method logic according to your requirements.
4. Once done, save and activate your code.

Step 5: Implementing GLOBAL Methods

If you want to define methods that are globally accessible (e.g., class methods that don’t depend on instance-specific data), you can create static methods.

1. In the Methods tab, when defining a new method, check the Static checkbox. This defines the method as a class method.
2. Implement the logic for this static method in the ABAP Editor.
3. Static methods can be called using the class name without needing to create an instance of the class.

Step 6: Activate the Class

1. After defining and implementing your methods, return to the main Class Builder screen.
2. Click on Activate (Ctrl+F3). This will activate your class and make it available for use throughout the SAP system.

Step 7: Testing the Class

1. To test your global class, go to transaction SE80.
2. In the Object Navigator, find your class under the “Repository Browser” and right-click to create a test program or use the ABAP editor to write a quick test.
3. Instantiate your class (if necessary) and call its methods to see if everything works as expected.