newb, stuck: text, basics

I would spend more time on google or hire a designer... their resolution specs are for your delivered asset to print.

So font can be any size (72 is arbitrary like in ms word size 12 etc)

make sure your artboard is the right dimensions.... when you export a jpeg or png thats where you can specify the dpi etc for the printing file.

Artboards can also show transparency if you want to see that ... you can also just open the export for web legacy window and see the transparency by previewing the png export there.

adobe illustrator is a vector program so you resolution is going to be set on any exports you make.

Can you ask RedBubble for a tshirt template?

First, you mention that want to combine your text with an image. According to Redbubble's User Agreement (User Agreement | Redbubble ), I believe that art needs needs to have been made by you. I'd recommend checking to make sure you have copyrights to that image.

Next, for the technical part, the site recommends using Photoshop. It's a raster based (think pixels or tiny blocks of color that make up an image) versus Illustrator, which is vector-based (think lines and shapes that can be stretched without affecting the quality of the image). You can use Illustrator for this project, but in the end, you'll be exporting a raster-based image.

By default the background in your workspace in Illustrator is transparent but the artboard will make it look solid. You can change how it looks when you work by going to the menu View > Show Transparency Grid. If you mean how do you make the background of the exported image transparent, you'll need to use a format that supports transparency. Like Monika said, JPEG doesn't support that, but PNG does. Let's get back to exporting after we make sure your document is set up the way you want.

Illustrator can combine raster and vector artwork--which is what it sounds like what you want to do. In this case, create your new document as 3873 x 4814 pixels and under Advanced Options set Raster Effects to High (300 ppi). Place your image by going to the menu File > Place... and navigate to your image. Once the image is loaded if you click, Illustrator will add it at 100% the size of that image, and then you can resize it. When the file to place is loaded, you can also choose to click and drag it out to fit your artboard. The widest it will be without cropping is 3873 which will make your placed image height 2577.993. Add your text wherever you want it on the artboard.

Because you'll be exporting your placed image with your text and your artboard is set to the size you want to export, now you can export it as a PNG. Go to the menu File > Export > Export as... enter the name you want to save. Set file type you want to save to PNG. A PNG Options dialog box will open. Set the resolution to High (300 ppi) and the Background Color to Transparent. Click OK.

1. not sure what you mean with this. You need to create a 3873x4814 pixels document. Don't care about the resolution. it doesn't matter. They need the pixels. You export at 72 ppi from Illustrator to get the same number of pixels.

2. JPEG can't be transparent. PNG can. You need Photoshop to edit the image.

3. Make text bigger when you want it bigger.