You can create a new table from inside the Delphi IDE by right-clicking on a TAdsTable instance and selecting "Create New Table...". Note you will need to have either the DatabaseName property or the AdsConnection property set before creating a new table.

Menu option to create a new table
You can ALTER an existing table from inside the Delphi IDE by right-clicking on a TAdsTable instance and selecting "ALTER/Restructure Table...". In addition to having either the DatabaseName or AdsConnection property set, you will also need to have the TableName property pointing to an existing table.

Menu option to ALTER an existing table
Note that the "Create New Table..." menu option is also available on TAdsQuery instances. This allows you to quickly create tables and then write SQL statements to query them.

Menu option to create a new table also available from TAdsQuery instances