hello guys, i can't progress in nightmare anyone wanna help me out or play together in general? I would love to get the awesome gear etc... but iam stuck atm in this difficulty. Iam a bit nooby so to say
Go to auction house, buy the weapon with socket (should be just few thousand gold), then buy Flawless Square Ruby (2-3k gold), put it in the socket and it will triple your dps.
You can buy Flawless Square Amethysts, put them into socketed armor and it will significantly increase your HP.
Starting from level 42 you can buy ilvl60+ items, using such item will make you a killing machine, oneshoting everything around you. They may be expensive for lowlevel, sort items by time left and use bid to buy them.
During the leveling processes, depending on the class you are playing, try to use abilities that have a form of crowd control to go with your heavier hitting attacks. Wizards can use Ice Armor and other types of cold spells to slow things down or freeze them in place, monks have an AoE blind that can buy you some time, demon hunters can use traps to slow things down while they run back and shoot from a distance, barbarians have an AoE stun, and witch doctors have lots of pets that can do most of the work for you.
Essentially speaking, you'll want a combination of "crowd control" abilities, defensive abilities (to take less or even no damage, very helpful versus bosses in solo play), some kind of buff (to increase your damage), and then one main attack and one resource builder.
Also, as suggested, don't be afraid to check the auction house every so often to look for a big upgrade. The drawback to the leveling play is that the gear does not scale very well as a whole. You still find items that are 10 levels below you in Nightmare, and even in earlier acts of Hell. If you're just having a good run of bad luck upgrading some of your outdated pieces, usually stuff in that level range (depending on it's overall power) will sell for only a few thousand gold.