so theres a lot on Japanese and nothing much on its presentation..

just wondering, is there a good way to speak Japanese from an English script/notes?
like writing stuff down in English, and then speak and expand out its ideas in Japanese

Ive got some practice down but fluency doesn't come easy.
also a recurring problem is translating what I have on the page into Japanese, but then not having enough time to think about new concepts

I'm not sure I got what you mean.

You're literally speaking about, for example, writing down a topic in english [Free Market Economy] and then proceed to expand it in japanese in a speech or something ? 自由市場というのは.....

If so, I'd like to ask you what exactly you're working on, or why is that necessary for you, (don't mean to be rude, I just want to contextualize)

The short answer to your question is "no." If you're giving presentations in Japanese, then you should prepare in Japanese.

When I do a seminar, I might create my first outline in English, but it's all nihongo from there. I'll write out the entire script (anywhere from 8-10 pages for an hour of content to 50+ pages for all-day affairs) and practice practice practice. Early on, I'll do a read-through with a native Japanese and tweak the content so it makes sense. After I practice enough so I know the content cold, I'll put the script into an outline and start practicing from that outline. Then I'll make slides and practice with the slides. In essence I memorize the content, and then "forget it" (put the content into my own, more natural spoken language).

You can adjust the length and complexity of your script and number of practice sessions based on the content and setting/situation of your presentation.

lol I wish I had the luxury to write in Japanese,
its a 7 minute preparation for a Japanese script
3 minutes presentation
impromptu
on a certain topic chosen out of 3 so it can basically be anything

I see. Are you already done? Let us know how it went. My suggestion still stands, though. Even if you sketch it out in English first, I'd switch over to Japanese asap. By the way, if you know how to do a mind map, it makes the note-making process easier.

Ex. Topic = Best Three Places to Visit in Tokyo

Tokyo (this won't look like a real mind-map...just an example)
- NO.1 --- Meiji Jingu ------ Most famous ------ Shrine
- NO.2 --- Tocho Bldg ------ Observation Deck ------ Free
- NO.3 --- Imperial Palace ------ Culture and Architecture ------ History

Then...the nihongo

"Tokyo de miru beki tokoro wo mittsu shoukai shimasu..." (or similar depending on your level)

Meiji Jinguu --- Tokyo de ichiban yuumei na ---- jinja
Tochou --- tenbou shitsu -- muryou
Koukyo --- nihon no bunka to kenchiku -- rekishi

Getting that far would probably take you 7 mins. to do the prep. Then you at least have a working vocabulary for your presentation. Depending on your speaking level, you can fill in the gaps with adjectives and verbs and grammar constructions that you know.

I think what they're looking for here is your ability to create Japanese sentences on the fly. If you have a habit of forming a sentence in English, translating it in your head, then speaking it, this isn't going to go well.