Non cluster index setup Help

Hi Friends,
i have below kind of table strucuture

Table_A (table_a_id int (PK), col_1 varchar(50), Col_2 varchar(50), Col_3 varchar(50),COl_4 varchar(50))

Please find below sample query
SELECT a.*
FROM Table_A a INNER JOIN SOme_Table_B b
ON a. table_a_id = b.table_b_id AND a.col_1 = b.col_1
WHERE a.col_3 = 'some value'
AND (a.col_2 is not NULL or a.col_2 <> '')

Could u please provide NON clusterd index structure for this usage of table. I already have PK on table_a_id of Table_A.

Sorry about the poor explaination.

Thanks In Advance
Parixitsinh