Weg is the keyword here. Weggooien (normal), wegsmijten (stronger) , wegflikkeren (plain rude), are all possible ways to say this. I throw away this book: Ik gooi dit boek weg. Ik smijt dit boek weg. Ik flikker dit boek weg. I toss this book into the trash: Ik gooi dit boek in de prullenbak. Ik smijt dit boek in de prullenbak. Ik flikker dit boek in de prullenbak. Anyway, the last one using "flikker" is a rude way but you'll encounter it quite a lot. If people are rude and want you to "piss off" they'll tell you: "Opflikkeren!" (Oprotten! Opzouten! Optiefen! etc. The worst of these would be "Opkankeren!" (kanker = cancer))

Thanks everyone for your answers :)

werpen = used in sports (when throwing is essential, like baseball, softball, etc) and to aim for a particular target. In Dutch, with baseball you can use "werper". Often used when throwing hard. Gooien = to throw with a curve, in children's play, and e.g. in soccer.

Both "gooien" and "werpen" can be used in daily conversations, but I think "gooien" is used more. To throw: gooien, werpen Vb. Hij gooit de bal. / Hij werpt de bal. = He throws the ball. To throw away / to throw out: weggooien Vb. Hij gooit de bal weg. = He throws the ball away.

try 'weggooien' Ik gooie het weg. Ik heb het weggegooid.