Don't put too much in your mouth at once. It'll make you want to spit it out again.
"Don't put too much in your mouth at once. It'll make you want to spit it out again."
「一度に口に入れ過ぎないで、また吐き出しちゃうよ」
* put: 入れる
* too much: たくさん、多過ぎ
* mouth: 口
* at once: 一度に
* spit out: (唾を)吐き出す(戻す、という場合は vomit)
* again: また、もう一度
ご参考になれば幸いです。