Is this for a separate shower or a shower/tub combo? The amount of fabric depends on what type and size of shower you have. I don't have any unusual or unique methods, but being the lazy sewer that I am, I use 2 yards(for the length)of ripstop nylon(60" wide, which just fits the width of our 'less that standard' tub/shower surround), make narrow hems on the sides, 1 1/2" hems on the top and bottom, make 10 buttonholes in the top hem(for the plastic or metal rings), and sew a few buttons or galvanized washers inside the bottom hem to weigh the curtain down. I don't use a plastic liner with the ripstop nylon. I have in the past used a tension curtain rod above the regular shower rod for a decorative valance. Hope this helps.

This is for a tub/shower combination. Actually, it's hardly ever used, and so I was hoping to do something kind of different and cool for the outside part and just have a plain plastic thing hidden in the back of it.

Can you think of a reason that a casing (like on cafe curtains) or loops wouldn't work?

Thanks so much for taking the time to help me.

No reason at all! Trying different things is what makes sewing fun. I just have a utilitarian view of things. I've used tab loops before and they work just fine.
You'll need at least 1 1/2 times the width of your opening for a decent gather(that's the usual rule for windows, anyway). Measure your length from the top of your casing(or ruffle if you want one)to where you want the curtain to fall, then allow enough extra to fold over for the casing and hem(this also depends on how wide you want these to be).
I hope I haven't confused you. Have fun with it and let us know how it turns out.

Thanks so much. Now...I just have to find the perfect material.

I probably have the same set up as you,or at least it sounds that way,tub/shower.

I buy 5 yds of fabric for mine and i cut that in half so that i have 2- 2 1/2 yd pieces.One of these i leave as is so it's 45" wide x the length(2 1/2 yds.. The other i cut in half lengthwise so that it is 2 1/2 yds long x 22 wide.Sew the 2 narrower pieces to each side of the 2 1/2 x 45'wide piece.You do this so you don't have a seam running down the middle of the curtain.

Now if your're using a big print,you'll have to get extra fabric so you can match the print.

As for the top,you can make a casing,tab tops or sew buttonholes to the top.

Good luck,it's very easy.Let us see your finish.
Kathi

To answer the "(This is because I have no idea how to put grommets into material and I think the casing or loop top might be more interesting.)"

Grommets are placed into material using a very special, and expensive tool. You're better off with the loop tops that have been discussed here. I bought one of those expensive tools and promptly gave it away after using it a few times to make outdoor camping equipment. Blesch!!!!

DonnaR/CA

Walmart has grommet packs for less than $5 in any size you want and it includes the tool you need. All that you need is hammer! Make a slit in your fabric just large enough for the bottom half of the grommet to slide into, put the top half of the grommet on, place the tool in the center and whack it with a hammer.

Here is a link that might be useful: grommet packs with tool included

Button holes are the easiest, then you can use hooks that slide easily. Plus, it is a good place to learn buttonholes. No one will be looking up close at them! Practice on some extra fabric! You can do this!
Kathy G in MI

I try to find a pretty single sheet.
use the large hem for the bottom of the curtin
measure the liner and allow for hems top and sides,sew hems. mark button holes to match liner. make buttonholes.
hook curtin and liner and hang as one. this way they move together. use spring rod and make valance (to match or
contrast) like a cafe curtin. hang as high as you think
it looks best for your room.
hope this makes sense.
gerryo

I came up with another solution recently! I want a Primitive country plaid curtain but do not want to spend $35+ on a shower curtain! So I bought 5 yards of fabric and plan to make my curtain with that. I didn't really want to mess with grommets and I can make button holes but they won't look really nice so I planned to do tab tops but while at the store, an idea hit me! I bought the cafe curtain rings with the clips on them! Then all I need to do is sew the sections together, sew around the edges and use the clips :)

I used to make them with a twin sheet and a cheapie plastic liner. Round buttonholes at the top (kathyg is right - they are super easy); hem to the length you want (or not if you need a long curtain). Also made matching window curtains and skirt for double sink with no lower cabinets.