I am writing this to guide someone who does NOT want to spend lots of real money. This has been more or less what I've done for 30 seasons, and I have 1 triple and quite many doubles.

You must have a combination of all these things:

A: Young fast training players who can improve as the season progresses (this allows you to keep up with the teams that have all 18-20yr olds)
B: Players with heavily skewed ratings (140% defense 0% attack, 140% P/M for a DC for example), this helps your cup draw.
C: Well established consistent players, since 1 loss in a KO match is critical, so up and down players are risky
D: Strong corner and free kick takers, this can be the same player, but it's critical
E: Get as many useful special ability as possible (wall, head, FK, corner), they don't count towards your cup draw.
F: A consistent game plan (ie. don't change your formation every match, find what works and run with it)

Important strategies to consider are:
A: Avoid playing your stars in meaningless matches, you wouldn't want him to pick up his 2nd yellow right before a critical match would you?
B: Keep training bonuses as high as possible
C: Power train the young players which are performing at high levels
D: Do not switch players mid season unless absolutely necessary
E: If you have 1 huge hole or need, fill it with a scout, but only as a last resort, and only if the perfect player is there.
F: Be patient, understand that a triple season won't be built over night, it might take several season of finding the right players to make the run.

Here was my triple team:
Treble winning tactics-bridgegothseason6.jpg
Vucinic, Belacivic, Weisser, Micu, and Cubillo were young fast trainers, the oldest (Weisser) was 20.
Cruz, Katsafaros and Mierzwa were skewed players.
Pujol and de Souza Soares I'd had for a few seasons and I trusted them, tho Pujol had a poor season.
Onyeike was a scout I added at the start of the season since I needed an MC and had no corner taker.

Cubillo had FK ability, Onyeike had corner ability so I dominated the set pieces.
Weisser and Belacivic had wall, Katsafaros and McLaughlin had head ability, so I defended them equally well.


Hope that helps!!