I think the one most important rule has been stated: be sure that the other player
knows that you are RPing evil, but as player are good.
To be able to RP with someone who is evil, you need to have a huge level of trust in that player. You must earn that trust, as player. You stated that in retrospect, your RP has been bad, but is improving. This means that you do not only have to earn trust, you have to first remove distrust. People have gotten to know you as bad RPer, so it'll be extra hard for you to convince them of the opposite, which is prerequisite for evil RP that is accepted. There are players whose evil RP I accept, and there are others which I ignore, based on my trust in their ability of properly RPing and not abusing their role. Likewise, there are players whom I ignore despite them RPing good chars, since I distrust them as players.
Additionally, it doesn't take an evil action to make a player feel not welcome, as player, or make you seem, as player, like a bully. One harsh remark may suffice, if it is mistaken for OOC, for whatever reasons.
Also, as has been stated, some people simply can't handle evil, especially not if done to their own chars. It is important to bear that in mind: with being good, you don't usually run chances of crossing lines with people, you don't usually make them feel bad. These lines are different for each and every player, and what they consider over the line ( = they're unable to enjoy it) also depends on the particular evil action. Be especially careful when doing permanent damage to someone's char. IMO, this must never happen without their agreement.
If they don't know you and your intentions, clarify them, as has been advised. I have come to not engage in non-nice RP with players whom I don't know yet. This is OOC, yes, but it is necessary to further the overall enjoyment of RP for everyone. I usually don't interact with them immediately unless the interaction is possible without hard comments. /me-ing can help, but eventually you must know what they can handle, and they must know that you're not OOC. When you're in non-nice RP with others already, then, of course, another player joining this RP will know beforehand, and also it'll be clear that they are not being picked on. At all times remember that you are RPing
with the others,
not against them.
Being evil means, as has been said as well, to have a goal that is purely selfish (it might involve helping an evil power of sorts, but only in order to gain something from that),
and to cross moral boundaries in order to achieve it. This applies to the power-hungry wizard as well as to the mugger on the street. It does apply to Hitler and his likes, but it does
not apply the average nazi or religious fanatic (they're usually just stupid, ignorant and desparate, therefore easily misled and misinformed by their leaders).
The way you go about reaching your goal depends on your char. As has been said, there is the brute one, and there's the slick, stealthy one, and different shades.
Now I'd like to comment on Sarrow's proposals:
1) contradicting people,
Not necessarily evil, unless you contradict them in order to cause confusion. Even this is by far not universal with "evil" people. You can do evil by conceding.
2) becoming socially prejudice,
Be extra-careful with this. Most people who are IRL are merely ignorant, not evil. Because of this, and the fact that it's so easy and thus so overused and shallow, it isn't usually a good idea. It easily reeks of being uncreative.
3) become outspoken and bring your views out in the open,
I assume this refers to letting other chars know of your evil goals? Otherwise, it's merely exercising free speech. (though free speech is often flagged as "evil" by the truly evil who seek to control public opinion)
4) convince people to take the \"wrong\" action during arguments or situations,
Be sure that it furthers your goal, though.
5) become impatient with people\'s disabilities or limits,
Make absolutely sure that it's 100% IC, and that it's received as that. Especially ensure that their disabilities or limits are not OOC, like non-native english speakers, or difficulties handling the I/O devices like keyboard and mouse, or bandwidth issues.
6) be less optimistic,
I can't see the evil there. It's more like a general trait, I'd say.
7) take roles that will benefit your gain,
Take
only those roles. If you must help the child get down the tree in order to get a chance to enter their house to spy or rob, or to "earn" their trust, or just to maintain a disguise, then do so. If it won't get you anywhere, don't.
7) use con-artist techniques during bartering,
If that's your char's style
dont help new people but either mis-direct them or shun them by laughing in their face.
Never, ever, follow that advice. Their being new is completely OOC, and therefore you cannot base any RP on that. Help them OOC-ly, and let them settle down. If you send a newbie in the wrong direction, that's plain OOC and just being a jerk.
9) Take the time to either despise beggars or poor people
Yes. Or make an act out of giving them something in order to gain unwarranted trust. Be sure to despise them when there's noone (except your inner circle) around to notice it.
10) Act as a spy and comitt treason within guilds
But make sure they know and agree OOC-ly.
11) Steal dropped objects when given the oppurtunity
Only with the exception about announcing it and acting it out in /me.
12) Decline people\'s request to share mob hunting
Absolutely not. The entire fighting system, with spawns and such is so ridden with OOC-ness that anything like this is OOCly being a jerk, not IC-ly being evil.
13) See friendships as partnerships or temporary co-workers
Yes.
14) Work for tria, not for free
Unless you have reasons to, yes.
15) See other\'s injuries and favors as pointless liabilities and only help people to use as blackmail or for valuable assistance later despite their usefullness
Yes.
