Stat Build: For the first 60 levels just follow the requirements for the x0 tests. They can be found by pressing C and look for the "Growth" bit. After that I'm not sure for blader, just go for whatever you need to get martialgear and katanas/blades
Skill Grinding is building your skill rank to get better skills at a lower level. The easiest way is to use Lv9 skills (For blader that would be Lv9 Flash Draw, Lv9 Impact Stab, Lv9 Force Stab) on mobs that you gain 0 exp from. That way your skills will go up but your level will stay low.
I recommend not doing it until you can get adept gear. The first ones you can get are:
Aramid Martialsuit of Adept Aramid Martialhelm of Adept Aramid Martialgloves of Adept Aramid Martialboots of Adept
You can also get Katanas and Blades of Adept (Don't know what they are called), bracelets (For Lv70+) and I think also rings and amulets.
Eskio on Demomen: In any case, the guy is full of rum. If anything he's a Molotov coctail in a vest.....with explosives strapped to it.