Yay! A hand sewn laptop case!
For those who live in Australia, it's for my free government laptop which I received this year. =D
The problem with the laptop case that was already provided was that there are 149 or so other people in the school with the exact same one. T.T
And thus, this laptop case was created.

Time wise, this took me something like 5 months to complete, but that's because I stopped working on it for 3 months or something while I was looking for a cheap 75cm zipper. XD This case would've been finished much quicker if I had a sewing machine tho...)=

Step 1: You Will Need:

Some stuff for this project. I used an old pillow case and some fabric I had leftover from previous projects. I'm not really sure what fabric the pillowcase is, but I know that the fabric for the lining is polar fleece. I used polar fleece because it's soft and cushiony and hopefully will prevent my laptop from being scratched. The green fabric I only used for decoration, so I guess that's not really important.
I also used a white 75cm long zipper.
Equipment would just be my normal sewing needles, thread, scissors and pins.

Sorry for no photo D=

Step 2: Start!

Because I used an old pillow case for my outer fabric, I had to first unpick all the stitches and then cut the fabric to size.
PLEASE MEASURE YOUR LAPTOP BEFORE YOU DO ANYTHING.
I wanted to make my plain white look a little nicer so I cut up some green fabric and tiled it. Like so.
I then stitched each one on with a blanket stitch.
Of course, this step isn't necessary and you are free to decorate your laptop case in any way you wish.

Step 3: Lining

To protect my laptop from scratches, I used some leftover polar fleece to line the case.
I cut two rectangles of fabric which, when overlapped by 4cm or so, could still completely cover my laptop, including seam allowance. This was because once I used up the seam allowance, the zipper was to cover the seam allowance area. If that makes sense.
So what happened was I pinned and sewed the two pieces of polar fleece together where they overlapped. The overlapping was intentional, and it's meant to be like extra protection for the back of my laptop, where the battery resides.

Step 4: Elastics

I wanted this case to be one that stayed on my laptop at all times, so I attached two lengths of elastic to the lining.
The elastic went from the bottom edge of the keyboard to the top of the laptop screen when the screen is flipped open.
Again, an unnecessary step if your goal is to simply create a durable laptop case.

Step 5: Zipper

The zipper was meant to go around three out of four sides of the laptop, so the one I used was 75cm long. Fortunately, I managed to get one for just AU$3 or something. I forget. But normally, they cost around AU$6.
I'd never really worked with zippers prior to the making of this case. So the way I attached this zipper may not be the conventional way, but it still worked for me so I don't really care. XD
What I did was unzip the zipper and then pin the whole thing together: outside pillow case, polar fleece lining and the zipper. I wasn't really sure what to do with the ends of the zipper, so I just left them poking out.
I sewed it all together with backstitch, because I felt it should be strong.
The corners were rounded as I sewed, but this wasn't something that I had planned for. It just happened. Which is why my corners may be a little lopsided.
When sewing through three layers of fabric by hand, one wishes for a sewing machine XD

Step 6: Finish

Once I'd sewn the zipper on and trimmed off excess fabric, I was basically done! =D
However, as you might note, the ends of the zipper were just handing about. It's not shown here, but I later sewed the ends together and covered them in a square of polar fleece.
I was very happy with the case, because it's a lot less bulky than the plastic case that was provided with the laptop.
I would love to hear any feedback!
Overall, this project was completed over a 4-5 month long period, but most of this was just me looking for a cheap zipper >.< So really, it only took a weekend to complete.
I say that if you're a beginner, don't have any qualms about attempting this because I'm just a beginner too. If I can do it, so can you.
So good luck and thank you for taking the time to read my ramblings.