Let me first say that I'm not a native speaker. So, I asked my Japanese sensei about your inquiry on "での". Here are his comments: 私は日本へ行った旅での経験について話します。 => This sounds redundant and a bit strange. So, here are the revisions: (BETTER) 1] 日本での経験についてお話します。(Nihon de no keiken ni tsuite o hanashimasu.) => This is formal and it sounds better than the casual one i provided below. (It literally means "I want to talk about my experience in Japan"). (Also CORRECT but...) 2] 日本旅行での経験について話します。(Nihon ryokou de no keiken ni tsuite hanashimasu) => This is also correct and it sounds more casual. BUT, having the word "ryokou" in that sentence will make it redundant. Here's why: 日本で => in Japan 日本での経験 => experience in Japan / literally means "Japan is the place where you had the experience". Therefore, "で" comes before"の" making it 日本での経験. 日本旅行での経験 => adding "旅行" (ryokou) is unnecessary because it is "already understood" that you're talking about the experience you had in Japan "when you were on a trip". Hope that helps. Happy learning! (^.^)

I got confused for a while because there's too much "の" in your sentence. Anyway, you might want to revise it to this: 私は日本旅行で得た経験について話します (Watashi wa Nihon ryokou de eta keiken ni hanashimasu). It's less confusing but it conveys the same message. As with the uses of "の", here they are: 1] it is used when nouns are used in the possessive manner example: 私の本 (watashi no hon) = my book 2] it can be used at the end of (usually informal) sentences example: どうしたの (doushita no?) = what's wrong? / what happened? 3] it is used in compound nouns/phrases example: 私の英語の先生 (watashi no eigo no sensei) = my English teacher. 4] it also used to indicate the position/location of objects or people example: テブールの下 (teburu no shita) = under the table Hope that helps. Happy learning! (^.^)