How to add custom attributes please help !

How to add custom attributes for categories?

There is no direct admin interface to add category custom attributes like product attributes

For that you need to directly add it in SQL, so before proceding take backup of below tables.
1) eav_attribute
2) eav_entity_attribute

Now add your new attribute in eav_attribute table for entity type id 3. To make it easy copy

Now after adding attribute in eav_attribute, please note inserted attribute id and run below
INSERT INTO eav_entity_attribute ( entity_type_id, attribute_set_id, attribute_group_id,

Where <inserted_att_id> is id of newly added attribute and <sort_order> for position of

Now your attribute is created and you can use it for each category.

Notes: After all above process you need to reindex catalog to fetch your attribute value.