ET can be a difficult game at first.
At first you should find a clan server (they usually have good admins), and I can recommend our server for that
You should play on few servers regularly so you become part of the "gang" and you are treated as a good player.
Example:
I see "mr.Man" connecting to the server, I don't really think anything about him and I don't expect him to be great player because I don't know him (he might be good but thats not what I expect at first).
But if I see "Pit" (one of the regulars on our server) connecting to our server I notice that and I'm glad to be able to play with such a good guy.
So even if you don't plan on playing day and night you should find a server where you will play regularly and if you are good, you will start to be respected by the players. The respect of other players is an important factor if you are going to play this game for a long time.
I would have propably stopped playing ET if I wouldn't have found the PLC server and the players playing there.
So you don't need to join a clan to keep playing ET, but you should find a server with good players and stay there. Game is a lot more fun when you know that you can trust the other players to try their best.
Other good thing is that you know that no one will be jumping down to the beach at the battery map ;D (if you didn't get it yet, you will get it once you have played long enough).
Playing in our server (or some other server that is like PLC server) makes you better player, you should listen to us when we are giving orders and advice to other players. It's often a good idea to listen to players who have played ET longer than you (Each of our members have played at least over 6 months).
You should also see what each class does and choose your favourite class (but don't limit yourself to one class only).
For example I prefer being an engineer and I've even been congratulated for my mine planting skills
This means that if you are planning to be an engineer you should see how I (or some other engineer) plays and take some ideas of that. If you want to be a field op you should see where other field ops call arty strikes and how much ammo they give (sometimes it's more important to give ammo rather than arty and vice versa).
This goes for all classes (medic, soldier, covert op) but I only listed my favourites.
You should memorize the maps, it can be very annoying if you lose the map simply because you got lost (especially true for bunker at the battery map). This is quite easy to do while playing by just following some other players.
You should also familiarize yourself with each classes special abilities (artillery, adrenaline needle, dynamite, mine spotting, ammo packs, health packs, etc...).
I'm not sure what would be a good starting class but medic is quite simple. You just heal and revive your teammates. It's especially useful to start following a good engineer if you are allies. Engineers usually have to go for the objective in order to win the round so you will get to know the maps too.
You should also be able to tell who is medic and who is engineer by their appearance, this helps in many ways.
These are the first things that come to my mind.
And my final sentence will be:
don't be a panzerfaust soldier, it is a class that requires skills that newbies don't have, leave it to professionalsGood luck for you