Are you doing bold, rapid, or standard synths? Each has its own strengths and weaknesses. If you just want to finish the synth and not worry about quality, then do rapids until it's done. I'd assume you have, but have you read the guide to the basics under wiki>crafting? That might help a little.
When it comes to strategy, I've noticed I rarely both synths when I "wait" after each failed attempt. When I succeed, I do another one. I've always stuck with rapid, since it doesn't seem to loose as much durability when it fails. I'd rather lose 10-12 on failed rapids then lose 20-30 on failed standard and bold attempts. I, personally, wont be worrying about making HQ products until I'm well over the required rank for the synth.
Hope this helps!
EDIT: Sorry, forgot to mention that the more +craftsmanship you have, then easier it will be. Also, make sure you're using the correct tool. Some tools are better for some synths than others. An example being using the wheel thing to make thread from moko grass as opposed to using the rusty needle.
Edited, Sep 25th 2010 1:40pm by swisa
*points above* I said in an earlier post what I'm using and when.
Rapid hasn't done anything good for me. It's awesome when it works, but failures consistently give me ~0-5% completion with 10-15 durability loss, no where near enough to finish the synth. And if it fails too much ... the sparks start flying and it only goes downhill from there.
As for HQ'ing ... I have no idea. I went back to level 1 synths and consistantly get the quality up to 150+ yet don't HQ. Oddly, once I was only in the 60's for quality and I did HQ making me wonder if quality really has anything to do with HQ'ing or if it's completely random.
I wear all the +craft/mag craft/control/output etc gear that I can.
EDIT: Speak of the devil, I just HQ'd undyed hempen cloth with a quality score of 36 and sparks flying everywhere. Edited, Sep 25th 2010 4:01pm by djocapn