Jon, I know you have stated you are new to backpacking and are interested in lightweight backpacking and of course have many questions so not to answer your question on sewing directly but you might find a lot of useful info in the following articles videos and websites I have linked below, and welcome to BPL:
Mike Clelland(NOLs instructor and author, his books are very good),he has some great free videos on lightening up be sure to watch(his clothing system,the entire contents of his pack,water treatment and part 1 and 2 on the dinky stuff for ideas).This is pmags Lightweight Backpacking 101  and The Frugal Backpacker – The $300 Gear Challenge andBackpacking: A Beginners Primer .These are some other articles and videos for you to check out
Backpacking for Cheap: Gear for the GearlessÂ
Backpacking Checklist (Gear List): 3-Season, 3-DayÂ
Lightweight Backpacking 101: An Introductory Manual for Lightening Your Load Today (1st Edition – August 2001)Â
Cheap Ultralight Gear ListÂ
Oregon Field Guide: Ultralight HikingÂ
Lightweight Testimony: Lighter, Farther, FasterÂ
Jamie Shortt talks about his progression and shows his gear list for each stage,
Lightweight Testimony: My Journey into Lightweight BackpackingÂ
Clever Hiker’s whole website is very nice, but here are a couple to look at
CleverHiker Light weight BasicÂ
CleverHiker Trail SkillsÂ
Andrew Skurka has a very good website with trips and gear lists and blog for you to check out
Andrew Skurka.com
here is a talk he gave at google
Ultimate Hiking Gear & Skills ClinicÂ
His book is worth checking out also
The Ultimate Hiker’s Gear Guide: Tools & Techniques to Hit the TrailÂ
You can get little repackaging containers (like the ones you see in Mike Clelland uses in his videos) many places including your local stores and pharmacy but here are some examples
USPLASTICS Â
USPLASTICS Â
Ultralight Designs Â
GossamerGearÂ
MountainLaurelDesignsÂ
You could make toothpaste dots like Mike C. shows or there are Archtek Toothpaste Tablets  so only bring exactly what you need in a snack size bag for any given trip instead of a whole tube and these are good for little things like pills, toothpaste, tablets ect. so you are not packing a whole bottle(you can also get these small repackaging bags very cheap at most pharmacies or craft stores ect)
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