Do i use my memory card when taking pictures of someone else?

I'm NOT a professional photographer, but i have a D3200 Nikon camera that my dad got for me, because i make some videos on youtube, and i also found that i Really love taking pictures. Well, my mom asked me to take some shots of her and then fix up some of her flaws (in her words!) using photoshop, and she really liked them and showed her friends at work, so now she told me that a couple of her friends want me to take their pictures and fix them up too, so my question is, do i just take their pictures using my memory card for the camera and then just email their pictures to them when I'm done? Sorry if its a stupid question, I'm just not sure how it works. Do photographers clients bring their own memory cards or something? But since I'm not professional or anything, do i just take the photos with my memory card full of my pictures?

Use your own memory card. How you deliver the images is up to you!

Have a class 10 card instead of class 6 ( class 10 cards are way better and faster)
And ya you should use your own card for privacy purpose.

Have double backups of *your* images on your computer, then wipe the card clean. You don't want to take any chances with you filling up your personal memory card and running out of space before you're finished with your clients.

And yes, use your own card.

Distribution is up to you. My photos are purely web-based with my watermark but since your potential photos are personal rather than public you might want to email them or buy a pack of cheap USB thumb drives to transfer your images onto, or burn them to a disc.

E-mail them the pictures. Use your own card. By the way, if you're doing this for experience and self-improvement, that's fine. However, if you're good enough to impress clients, then somebody asking you to do it for free is taking advantage of you. My mother's co-workers would not be among those that I would do it for as a favor. I'm just saying.

The memory card is a tool and considered part of the camera. Use only yours all the time. Since you're doing this for free, your distribution of the end product doesn't really matter as long as your mom's friends are happy with it.

You are correct. Use your own card, then transfer the shots to your computer. Once on your hard drive, then you've got a few options.
1. You can burn the images to a CD or DVD and mail/deliver the discs to them.
2. Email them - but this can be a problem since many email services limit the size of attachments.
3. Create a Drop Box, or Google Drive account. Place the photos in a folder and send an invite or a link to the folder to your clients. This way they can get full resolution images and you don't spend any money on CDs, DVDs or postage.

I've never heard of anyone (at whatever level) use someone else's memory card. It simply doesn't make sense since you'd have to format the memory card to you camera's internal program anyway. Yes, by all means, USE your own memory card, and reformat it after you've backed-up your images (hard drive and another extermal hard drive… "belt and suspenders" to ensure against error and/or corruption that may occur when you least expect it); that will ensure you do not fill up the memory, and allow you space for new images. It's not a "stupid" question. When you don't know, it's best to ask and be better informed.