I've played Cassiopeia for a long time, but its very hard for me to 1v1 people with CC (which almost every mid has)

Any tip? D:

Sorry for crappy English.

The best Cassiopeia tips I can give are mana regen and boots.

When I play Cassiopeia I take mana regen seals AND glyphs, plus mana regen in my masteries. With all of these you can regenerate the cost of her Q before it is off cooldown (if you have all 5 stacks of your passive). At the start of the game I pop my Q 4 times in base so I don't lose any mana, then I make sure to pop it every 4 seconds so I don't lose my 5 stacks. Even if there's nothing to hit, I pop it randomly. Because with all that mana regen and 5 stacks of her passive HER Q IS FREE.

Since I have enough mana regen in my masteries and runes and I don't need to buy any (no need for doran's!) I start with boots. Most mids who have CC are either short-range (Annie, Ryze) or have skill shots (Ahri, Lux). The short-range is countered by careful zoning. Keep popping your Q's all day long and they're afraid to get in range. The skill shots are countered by the boots. The extra 50 movement speed will help you side-step almost any skillshot. Of course this takes some practice.

Your English isn't bad Yon, in fact you have better English the half of the people who claim English as their first language. With Cass you basically want to zone them and force them out of lane. http://www.lolpro.com/guides/game-play read the zoning guide. Cass has awesome range and she can safely harass and poke without really any fear of reprisal. Focus on creeping, and do what's called counterhitting. You can’t Deny in LoL, but you can counter hit – which is more difficult and just as important. Deny was a concept in Dota where you could actually last hit your own minions, preventing gold and experience from the enemy champion(s). In LoL, this is not possible, however a new mechanic presented itself – counter hitting. While seemingly difficult, you will need to focus on the health of not only your own minions in lane (so you can effectively last hit), but also the health of allied minions. When you notice that an allied minion is very low and the enemy champion is about to last hit it, you will want to concurrently hit the enemy champion. The enemy champion cannot hit you and the creep at the same time. During the automation when they are going to attack the minion, they will also take harassment from you. This mechanic may not be effective on all champion match-ups in lane, but is almost always effective in a ranged AD versus ranged AD scenario and is often the case in AP versus AP and can be used in a ranged versus melee set-up lane matchup. Other scenarios might cause too much minion aggro for this to be effective, but it is an important mechanic to master. Practice it over and over until you can consistently counter hit. The best champion to practice this on is Tristana, just based on her animation and range.

so far as ive seen, just try and harrass. your Q is insane for that, especially since she has such a high ap ratio. you dont need to bother hitting a few twin fangs after. also, be more agressive than you would be under normal circumstances. but dont worry too much about mana, so long as you got some mana regen seals. though an archangels smite is insane on her, because she is very much a spamming champion. last, i absolutly agree with grollm. i have found that it is kind of annoying hitting her Q on a moving champion, but it should be easy to hit them with it by using his strategy.