The most important part is to have fun and make your character look the way you want. Pick weapons/armor that look cool, then build to suit them. Any build that isn't extremely bent towards STR or AGI will work with tons of gear so you can always change your mind later.
If you really have no idea/preference, go for a balanced 21/18 or 18/21 build. While you play you will find what attributes you wish you had more of, and which feel like wastes of time. For an actual level 30 build, here's my favorite:
24 Strength
15 Agility
8 Powerstrike
5 Athletics
5 Weapons Master
5 Shield
5 shield is enough to let you try any shield except the steel shield (which is a very niche item for only the most dedicated of shielders). Try out all the shields that you think look cool. Light to medium chainmail armors. 8 PS gives a hefty bonus to your attacks, which I feel is vital if you want to be a shielder. You will often act defensively, so you want those hits you do make to be worth the swing. 24 strength gives a health bonus a little below 18STR/6IF, but the tradeoff for 3 more PS is worth it. That's almost 50% more bonus damage from skills. You might be able to get by on 3 or 4 WM, but 5 gets you on-par with others as far as swing speed. You could even sacrifice some WPF from 1H to hybridize into 1H/pole if you want to try shield&spear. If you want to add a crossbow I'd suggest a higher AGI build since xbow eats up a lot of WPF compared to a secondary melee skill. Last of all, 5 athletics is plenty. As long as you keep up with a group of teamates, you will be a massive boon in teamfights. Draw attention and attacks away from your teamates with pole/2H weps and no shield. Punish enemies who turn away when you stop blocking.
I really liked 18/24 with a buckler, but that's not for everyone. And you need to be 32+ to get near completion of your build.
I also recommend trying out 24/15 and 15/24 builds on a skip the fun character. You might find that you like a more specialized build...
