Considerations before adding new fields
We recommend putting in a support ticket before adding new fields, for the following reasons.
1- Your new field may be on our roadmap, if so we can let you know as you may want to wait before adding the new field.
2- Some fields, like certain picklists, drive special functionality and if changed could break something, (Order Types, Line Types and sometimes Statuses) We can let you know if there are any restrictions before proceeding.
3- Any new fields will not show on documents by default. Custom documents are required to add field, and we can direct you accordingly.
4- Using the correct field type is very important, so we can help you with the proper selection of the field type depending on how you want to use it
Enter the Setup Menu
Enter the Object Manager
Select the object to add a new field
Select “Fields & Relationships”
Select the field type
Field types determine what type of data can be added to the field. For instance, a text field will accept any type of text. A Picklist field uses a pre-determined list of fields to pick from.
Additional information on field types may be found here: https://help.salesforce.com/articleView?id=custom_field_types.htm
Enter field information
1) Enter the field label. This label is what will show to your users on the screen.
2) The length is the total length of the field. Not all field types will have this option, but it is shown here since the field type selected was text.
3) Enter any help text for the user. This text will show next to the field on the page and can give users helpful information about the data that should be entered.
Select security levels
This screen allows you to select what profiles are allowed to see this field. While security is a complicated topic, this screen allows you to set the visibility of the field per profile.
Add to page layouts
The Add to page layouts screen allows you to add the field to specific page layouts. Since there can be many different page layouts for different configurations, your screen may look differently.
Add or Modify page layouts (optional)
Once you have added the field and added it to the page layout. By selecting “Page Layouts” on the left side of the screen, and selecting the page layout you want to modify, you can have greater control of the placement of the field.
Modify the page layout (optional)
Using a simple drag and drop editor, select the field to add from the palate at the top, or move the field around in the main page pane.
Additional information can be found here: https://help.salesforce.com/articleView?id=customize_layoutcustomize_pd.htm