By all means get green and red packs, look at each and every player's form and u'll notice some do very well in one competition and average or poor in others, then earmark dem for dat competition. Also check who has d most yellow card and is on d verge of suspension DO NOT play them in the coming last leg before the finals (i.e if u r sure of qualifying) - so u wont have ur best guys suspended against ur cup/cl finals. I think the above criteria will help u mix ur team in preparation.