YOU SAID:

I've been wearing my bathing suit as a substitute.

INTO JAPANESE

代替品として私の水着を着用しています。

BACK INTO ENGLISH

As a substitute to wear my bathing suit.

INTO JAPANESE

私の水着を着用しての代替として

BACK INTO ENGLISH

As an alternative to wearing my bathing suit

INTO JAPANESE

私の水着を着ての代替として

BACK INTO ENGLISH

As an alternative to wearing my bathing suit