My technique is to put all of those queries at the end. Then I can enable the test queries or the final result query as a block of text and only be concerned with having patched out the queries not to use. For instance to test the content of "OldPeople":

WITH

People AS (

SELECT 1 ID, 'Joe' FirstName, 'Smith' LastName, 21 Age, 'Male' Gender UNION ALL

SELECT 2 ID, 'John' FirstName, 'Smit' LastName, 32 Age, 'Male' Gender UNION ALL

SELECT 3 ID, 'Jo' FirstName, 'Schmit' LastName, 43 Age, 'Female' Gender UNION ALL

SELECT 4 ID, 'Joanne' FirstName, 'Smith' LastName, 54 Age, 'Female' Gender UNION ALL

SELECT 5 ID, 'Juan' FirstName, 'Smithe' LastName, 65 Age, 'Male' Gender

)

,

OldPeople AS (

SELECT * FROM People WHERE Age > 50

)

,

Men AS (

SELECT * FROM People WHERE Gender = 'Male'

)

--select * from People

select * from OldPeople

--select * from Men

--SELECT

-- o.*

--FROM

-- Men AS m

-- INNER JOIN OldPeople AS o

-- ON m.ID = o.ID