If you have any tips that you think would be a good addition to this list, please e-mail them to Instigator.
Save your training points until level 5 when you can use them on specialization paths. They have little use prior to that level and you don't want to accidentally put them into the wrong paths.
Don't forget to do tasks. Highlight a NPC and type help and see if he has anything for you to do. Tasks generally bring in good experience points and can help you level faster.
Along those same lines, if you are hunting in an area near any guards, ask any named guard for a task. Odds are, they will ask you to kill something you planned on killing anyway, and will give you a nice reward for it.
Hotkey the sprint button and have it ready at all times. If you get in trouble, sprint towards the nearest guard area. If you time it right, you should be able to keep far enough ahead of the Mob that it either gives up or you get to the guards before it gets to you.
If you can, try to bind in an area that has a healer, even if it is a little further away than other bind points. You're going to want to raise your constitution up anyways, so you might as well reappear near the healer.
Take some time to explore the main city of your realm. There are a lot of things available there that are not available anywhere else and you want to know where everything is.
Keep an eye on your equipment and don't let anything decay too far. Get used to the idea that your weapons and armor can wear out and make sure you visit a smith (or use your tradeskill) to repair them.
Make sure you click on everything to see their aggression level. Don't assume certain Mob types never attack. As you go up in level, higher level Mobs that look similar to the ones that were passive at low levels often become aggressive and will attack on sight.
Do quests! The economy of Camelot is very very tight. If you're grouping all the time, it's unlikely you'll ever have enough money to keep yourself in level appropriate equipment. Doing quests can result in some pieces of armour or weapons which offset the cost of buying that piece.
Most higher level quests are best if they're not done all in one sitting, since they can tend to take you from one end of the world to the other, and back again. The epic quests which start at level 15 are a good example of this. Make sure you get the quest, and then do the various parts whenever you find yourself in the neighbourhood.
Money is almost as important as experience in Camelot. If you're hunting creatures which drop no money or loot, you're doing yourself a disservice a you'll find youre equipment to be subpar as you level up. Always ensure that you're hunting creatures which give reasonable loot.
Grouping is an excellent way to get experience. A simple healing class plus melee class can result in twice the xp that either class can do alone. While it's great that solo is permissable, the game can be alot more fun when you group.