DECLARE @role VARCHAR(50)
DECLARE @targetSchema VARCHAR(50)
SET @targetSchema = 'dbo'
SET @role = 'MyUser'

SELECT 'GRANT EXECUTE ON ' + SPECIFIC_SCHEMA + '.[' + SPECIFIC_NAME + '] TO ' + @role + CHAR(10) + 'GO'
FROM INFORMATION_SCHEMA.ROUTINES WITH (NoLock)
WHERE SPECIFIC_NAME Not In
(SELECT o.name FROM sys.database_permissions p WITH (NoLock)
INNER Join sys.objects o WITH (NoLock)
ON p.major_id = o.OBJECT_ID
INNER Join sys.database_principals u WITH (NoLock)
ON u.principal_id = p.grantee_principal_id
WHERE u.name = @role)
AND ROUTINE_TYPE = 'PROCEDURE'
AND SPECIFIC_NAME not like 'sp_%'
AND SPECIFIC_SCHEMA = @targetSchema
ORDER BY SPECIFIC_NAME

Just change the @targetSchema and @role variables and run it. The results will be a list of procedures on the current database which don’t have execute permissions assigned to the indicated @role. You can then copy those procs you want to grant execute on into the query window and execute them.