While the rest of the project was fun and lovely, the flat sketches are the real meat of the portfolio. These tell the future employer what they really need to know: can you use Adobe Illustrator? This is especially important at the assistant and associate level. As beautiful as your hand drawings may be, the flat sketches are really what you're going to be doing in the day to day of your job.
With flat sketches, more is actually more. The very minimum you should have would be five. However, ten wouldn't be overkill in any way. In fact, if you have enough time, you should draw flats for every garment in your five looks.
Some things that get you bonus points with flats:
Don't go overboard adding extraneous details to the garment just to get some complexity in there. However, a piece of outerwear with topstitching, buttons, closures, back neck taping, and any other sort of functional details is totally acceptable.
If you don't know how to make brushes in Illustrator, you should go ahead and learn. It's pretty fun and cool, and if you use (again, reasonable) brushes on your flats, that displays some good knowledge.
Now, to be safe, you probably want to present your flats in black and white form. However, you can add plenty of fun textures with the use of fills. Again, if you don't know how to make fills, go ahead and learn. There are plenty of tutorials online, and it's super fun.
4. Front and Back Sketches:
This is fairly mandatory, but it never hurts to mention it.
Some things that will take points away:
1. Incorrect stitching or no stitching at all:
When in doubt, look at a real garment. You need to know about construction.
2. Incorrect seams or no seams:
Again, look at a real garment.
3. Lack of Closures:
How is your customer going to get in and out of her garments? (note: this isn't a problem for sweaters and cut and sew knits)
When you've made all your flats, you can add them to your project in one of two ways:
1. On one side of a two page spread, have your fully rendered drawings. On the other side, add the flats for the garments in that drawing.
2. Just add all your flats at the end of your project in their very own little section of flats. This is the way I usually arrange my projects so that the technical drawings don't detract from the drawings.
Now, you have all the parts of the fashion project, and you're ready to go! You should be proud. Scan it, and send a pdf to your mom, if it's not already in the computer. That's what I do. And then drink a coke and eat a whole bag of riesens without stopping. That's also what I do.