First-- you can buy extra hook carriers so you are not limited to the number that come with the rods, though you probably won't need them.

Second--For full drapes you will need 3x the width of the window or the width you want the finished drapes to be if you make them wider than the window. If you make five finger pleats you may need more. You will need the length you want the finished drapes to be plus an extra header width and a good sized hem. If they are full length drapes I usually put a 4 or 5 inch hem, but it depends on your material. Don't go too small or they look cheap.

To make pinch pleats. You need header tape. Remove the selvedge edges from the sides. Put the header tape on the top end 1 1/2 inch in from the edge--stop 1 1/2 inch from the other edge and cut the tape. Fold the material down over the tape 1/2 inch and sew. Make a 1 inch hem on the sides. Now fold the tape down so the tape is enclosed in the material and pin.

Now comes the measuring. I prefer a 3 finger pleat. If I want extra fullness I make the pleats closer together. You need 1 inch for each finger--a 3 finger pleat requires 3 inches. Measure 1 1/2 inches from the edge and make a mark. You can use chalk, sewing pencil or even a soft lead pencil. You don't need a big mark , just something you can see to mark where the pleat pocket is.

For a 3 finger pleat with 2 inches between pleats---Measure the curtain across the top. Take off 6 inches--for ends and pleat at the end. Divide the remainder by 5 and see how it works out. You may have to increase or decrease the end measurement or make it 2 1/2 inches between pleats.now measure 3 inches and make a mark. Now mark the distance between the pleats 2, then 3 for pleat repeat across the top.

Sew your pleat loops from top to bottom of thr tape so you have one big pleat. Now pleat the loop and finger press into 3-- 1/2 inch pleats and stitch across the bottom of the pleats at the bottom of the tape.

If you want to make it easier then buy pleater tape that has strings you pull to pleat them. This makes very nice pleats all across the drape. The tighter you pull the strings the fuller the pleats. You sew it on flat and then pull the strings and tie them off.

I suggest you get hooks that go the full length of the tape in both cases. Little hooks tend to make the tape fall forward on top and if you put them higher the rod shows.

I also suggest that you look at rods that have wooden rings on top and clip on to the drapes. They are as easy as a shower curtain to open and close.

The link below is very good and it will give you a lot of info about making drapes

Here is a link that might be useful: tutorial on drapes

Myrna gave you great suggestions and I often refer to the tutorial she suggested and use the 4 or 5 inch hems as she mentioned. If doing unlined I often use a double hem, sometimes putting a few weights to help them hang/drape nicely. Have never used the pleater tape with the strings, but stay away from the pleater tape that you use the 3 or 4 prong drape hooks, the tape looks like canvas with slots for the special prong hooks, my friend used this and when she had them dry cleaned the tape shrunk and the pleats were never a tight look.
Agree on the type of hooks Myrna mentioned.

I have had used Clip Rings and the Grommets.

Clip Rings: (Had these in Family Room on a large Bay Window and double window) You have to reset/measure the clip rings after cleaning or washing. They look good when hung but do not stack back quickly have to fuss over them a little.

Grommets: (Did these few years ago for Son's Florida Room) The buckram header usually about $8.00 a yard, the Cover either metal, plastic think they are about $2.00 for each Grommet Cover, they sometimes do not snap into place easily. When dry cleaning or washing have to watch they can scratch up. When you close them they often remind me of an cheap accordion door loosing the pleating effect even if adding for extra yardage fullness.

Used Double hems on both, The Grommet ones look great when open, do not like the look of rings when closed even though the Rod and Grommet color matches.
The Clips on the size of windows I did and the amount of fabric, was a chore to launder and re-measure for spacing on the clips.
On both my son's and my windows had rods that were not adjustable, if using an adjustable rod the Clips or the Grommets could hang up on the one part of the rod or support brackets.

I am not trying to discourage the use of either just wanted to let you know my experience with different types of headers
Good luck on what ever you choose it is well worth the effort, the cost of custom made is outrageous

Pattie:
The tape I mentioned with strings is nylon or some synthetic. I have used it on some curtains. It doesn't shrink at all, and it stays stiff after it's washed. There are different pleating designs and they look quite good.

I know what you mean about the pleater tape with the 4 pronged hooks. I used it once years ago and it does shrink. Not only that but it looses it's stiffness.