Dressmaking can take a while to get going with...well as in actually making something you'd want to wear and that fits!
I've found it easier since getting cutting mats and rotary cutters and using metal washers as weights, instead of using needles to pin down the tissue pattern pieces.
Also with sewing, you'd be best starting off with make simple things like simple bags, pencil cases, then move on dressmaking, get a beginners' sewing book...I bought 'Sew Everything Workshop'.
IMO making things 'off the top of your head' is not an easy option, I've been sewing 7 years and couldn't do that!
Like you say, if you had better internet, you can get some great Youtube videos on simple skirts with just wide elastic as a waistband.
You'll get better results if you persist with the patterns.
If you can get hold of any Amy Butler sewing patterns for bags etc, I found them really great for advancing my sewing skills, because the instructions are so thorough...unlike dressmaking patterns which usually expect you to know what to do, giving only basic instructions (unless you buy from an independent designer like 'Sewaholic' who have better step-by-step instructions)
Things not fitting was a BIG problem that nearly made me completely give up, I bought the 'Palmer Pletsch' books of pattern fitting which have really helped...especially with knowing which size pattern to cut out, how to measure myself.
Always start with really simple patterns, that don't need much fitting, such as a full skirt, smock style dresses.
When you've got better internet access, I really, REALLY, recommend Craftsy classes...they are ACE!!! I've bought their classes on repairing clothes, watercolour painting, knitting...I'm just in love with them
. You can keep replaying them and ask questions. I've seen some beginner sewing classes on there....
Don't give up! 