While working on a performance I realised that I needed to work a bit bigger.

What I'd like to do is ask 3 people in the audience to call out a digit between 0 and 9. After this I start some patter and then reveal that I predicted the 3 digits by showing a big piece of paper where those 3 digits have been printed on.

Although I don't expect people to just plainly explain it here in this topic, I would greatly appreciate it if someone could point me to the right direction.

Thank you in advance

The best way to accomplish what you have described would likely be with a one-man "confabulation" type routine.

I have been working on something quite similar recently, and I use the Wonder Unit that is included with the Jerry O'Connell Plus Wallet. Essentially, the routine revolves around implanting thoughts in three participants' minds, and having them say which thoughts first come to them. Example: Spec. 1 says "lightning," Spec. 2 says "hibernation," and Spec. 3 says "Jupiter." I write each response down as it is provided, and after they are all written down, I put away the pad and paper, and take out my wallet (which has been inside the inner breast pocket of my suit jacket, which has been away from me, resting on a chair). When the wallet is opened, there is a zipper inside, which is unzipped to reveal a pocket with an envelope. The envelope is removed, opened, and a small white card is inside (about the size of a business card). This is given to a volunteer to be read aloud to the rest of the audience.

Upon it is written, "Later today, I will attempt to implant three random thoughts. There is no guarantee that I will succeed, but if I do, the three resulting thoughts will be LIGHTNING, SLEEP, and JUPITER. I hope for success."

This is easy to adapt for a routine such as the one that you've described. I highly recommend the Jerry O'Connell Plus wallet for this type of act, since it accommodates the "confabulation" plot for a solo performer, and it does so very well, which is a rarity.

That said, the main point that I want to get across is this: You don't necessarily NEED to have everything large in order to make a routine play for a large audience. Simply having one member of the audience on stage to read the prediction makes the whole affair much more grandiose. Naturally, it is unwise to use small props for every effect, but when performing mentalism, the best large props are participants on the stage. I would advise that you forget about making the props larger, and simply involve more stage participation.

However, it can be good to provide a point of focus for the audience during some routines, especially ones involving predictions. If that's your aim, I would simply use the same routine that I've just described (or something similar), and simply "doll up" the prediction case (perhaps a locked box or sealed bag for my purposes), placing it somewhere that is easily seen, such that the audience knows it has been in view since the routine began.

Thank you so much for the suggestion, I'll look into it. I haven't gotten a wallet for shows yet and it seems I should

I'll add some context to my question and also a idea that i thought would work (although it's still in development)

context: I'm giving a show about how people are not as random as they think and start with a NW number prediction. This prediction is read by one of the people in the audience and then a start explaining how numbers work in our minds (which is partially based on real science). After that i'd like to prove it by predicting multiple numbers in a row.
Because of the NW prediction already been read out by someone, I wanted to show this differently.

My current idea (before i read Satanica's post): Instead of printing the numbers on one sheet of paper, i'll have business cards with numbers printed on them, large enough for everone to see from a small distance. Using the OA principle I'll continue asking for numbers until they say the number i started with.

although this can be easily done with playing cards and some sleight of hand... i'm still figuring out a way to present it very open.

.....now i'm going to read about Jerry O'Connell Plus Wallet

Here is something to keep in mind:

The Jerry O'Connell Plus Wallet is wonderful, but it's not worth buying ONLY for the Wonder Unit. If you want to perform a Card to Wallet routine, this is absolutely the best wallet to buy (it isn't made as well as it used to be, according to rumors, but it's still the best - mine is a new model, and I haven't had any issues with it so far). Due to the price, I would only recommend it if you plan to use it as a Card to Wallet as well as using the Wonder Unit. There are plenty of other ways to perform a confabulation-esque routine, and with a little thought, I'm sure you could work out a method that is just as good as the O'Connell Wallet, but better suits your needs.

I have an idea that involves spending about $15 as opposed to the $100 you'd have to lay down for the Plus Wallet: P**-S***, use CP to get numbers from three people, showing them the large board containing the prediction (which should already be on stage). Once you know the numbers, simply write them on the appropriate side of the board. Proceed with performance. No risky moves, nothing to suspect.

One more method: third hand. Think about it.

Alternatively, you could combine the two.

If you want more clarification, I'd be happy to provide it. Let me know.