Mostly you look for early comb development, boys will get pink earlier and than red by 8-10 weeks generally.My silver laced has a nice round puffy crest, just as puffy as my white crest black. What other things do you look for in a male?
In non bearded individuals the boys develop wattles earlier too. So that's what I look at in the laced varieties.
The white crested varieties are easier to tell by crest shape usually.