Play warm up matches to get your players' fitness/energy lvl to
100 ASAP. Den use 4-1-2-2-1 formation for Chelsea most of da time.
No need Sheva coz Crespo is more den good enuf. No need ballack
too. You wan get Ronaldinho.
Training wise: get all your tactics "build up play, short pass,
counter attack, etc" to full 1st then train individually. Until now
I still no idea how to improve player abilities but seems you put
them in 1 specific training regime then you can see significant
results.
And play as many matches as you can. Your players grow most from
there.