In this guide I will discuss what a good group consist of and why. I will also talk about what each persons role is in the group.
For the first few levels as long as you have a cleric you should be able to finish any lvl 1-3 quest without any real problems. I would suggest to have a backup healer as well a cleric such as a bard. I play a bard as my main character and if played correctly you can heal better than a cleric at lvl 3. If I were to have a perfect group this is what it would look like.
Sorcerer / Wizard
Fighter / Barbarian
Fighter / Barbarian / Pally
I know I left out a ranger but that is because they really do not have a huge place in groups. They are a ranged character for the most part but so are bards. A bard at lvl 3 with a Heavy Repeating Crossbow will out damage a ranger easily.
Now lets move on to what each person in the group does and how to do it effectively.
Cleric - This class is usually the primary healer. The reason I say usually is because at my multiclassed bard had 380 Spell points at lvl 2. This was accomplished by combining the bard with a sorcerer. I could heal 38 times with cure light wounds or repair light wounds (as a sorcer I took this spell). There are multiple kinds of clerics. There is the complete support cleric who has a high wisdom and high charisma. There is the battle cleric who has a decent strength and then neglects charisma. If you were the complete support class you would stand in the back of the group throwing out heals when needed and keeping bless on the party. A battle cleric would charge into battle and swing away only stopping when someone was severely injured. Either way you will still be an effective member of the group its just a matter of preference of play styles. Oh and make sure you have restoration up. Your party can take ability point damage quite often in quests level 3 and up.
Rogue - The rogue is the master of sneaking, disarming, lockpicking and searching. As a rogue you will be moving ahead of the group while sneaking. Make sure you have a high spot skill as well as the main skills. This will give you a heads up when you are approaching a trap. Once you find the trap tell your party instantly. Make sure you address this issue before entering a dungeon as new type characters are not used to traps in MMO type games. You will also probably have the highest search skill in your party. If you see something fishing and think there might be a secret door there search around. I have found many chests and rest shrines becuase i had a hunch there was a secret door. It is pretty obvious where the secret doors are. They look like an alcove with steps up to them and then there is a wall. If you keep you eyes open they are really easy to spot.
Sorcerer / Wizard - You are a crowd control class for the most part. With your burning hands at lower levels you can wipe out a room full of kobolds with just a few casts. At level 3 make sure to pick web. To finish a large amount of the higher level quests are almost impossible to finish without it. You could even get an invite into a group a few levels higher just because you have this spell and the loot in those quests is incredible. As far as how to play this class you want to stay behind your fighter but close enough to get off your burning hands and hit the highest amount of monsters. At higher levels you will become more of a ranged caster but for right now you will probably have to stand near the front.
Fighter / Barbarian / Paladin - This class can be played so many different ways. With the option of going two handed, two weapon, using a shield or taking the heavy repeating crossbow feat the sky is the limit. To better understand these combat tactics check out my other post "MELEE AND RANGED TECHNIQUES AND STRATEGIES. You can find this in the strategies section.
Bard - A bard is the ultimate support class. They can be a melee fighter but i prefer to use ranged attacks. Taking the heavy repeating crossbow feat is a huge help and will allow you to put out a massive amount of damage. At level one make sure to pick cure light wounds as your first spell. This will make you a valuable member of any group. My bard is currently level 3 and has over 400 spell points. How the heck did i get so many you ask. Well I took sorcerer at level 2 and this jumped my spell points from 90 to 300 instantly. Also using your bards songs is a huge help to the group. Your inspire courage song will give everyone in the party a bonus to saves, to hit, and damage so make you you are using these. I have seen too many bards sitting on their mana and songs as if they holding on to them will somehow give them more xps or loot. If you have skills use them. Do not sit on your abilities. When you hit the next rest shrine they will all come back. Also ask around your group and see if anyone has any spare wands. Wands are a huge help to the bard.
So now you know what a good group looks like you need to know how to find one. First make sure you have your LFG on. To do this just type /LFG. This will make a golden icon show up over your head and let everyone else know you are looking for a group. You can also search for a group using the social tab. Open up the tab and go to the Group section. When you open it up you will see a ton of different names and what those people are looking for. In the comments section you can also find what quests they are running or looking to run. Most people put that information in the comments but not all. Also being in a guild is very helpful for finding a good group.
All in all grouping is the only way you will get any good loot or experience. So make sure you find a good group and stick with them. Finding a quality group can be difficult sometimes. I would also suggest adding the better players to your friends list and talk to them when looking for a group. It is very possible they have an opening.