Life Lines!

I mentioned how thankful I was for life lines online recently and thought I might demonstrate how and why I find them useful.
I use them in a variety of projects as I'm not great at fixing mistakes, especially in lace or cables, basically if it's not stocking stitch I'm stumped lol
I use them in socks after the cuff, after each pattern repeat (if doing lace/cables), before the heel, after the heel, after the gusset (if doing heel flap and gusset), and before the toe decreases. I find these specific points good for life lines as they are places something changes and so if I drop a stitch early in the leg and don't know how to fix it (if it's not stocking stitch) I can rip to the cuff and start again, the same goes for the other places, I once messed up a heel and panicked till I remembered my life line would stop me needing to unravel the whole thing lol Unfortunately the time I used the wrong needle size I hadn't used a life line and ripped back a whole half sock and started again lol
I use them in shawls after each section or if not built using sections every inch or two depending on number of stitches on the needles. This comes in helpful with shawls like the trillian every inch or two and the hitchhiker every couple ridges, and the demon enough for her shawl after each lace repeat, but on the eleventh hour shawl with short rows I'd have wondered where to put them if the pattern itself wasn't broken up into sections. For a basic triangular shawl, if it is alternating between a pattern and garter or stocking stitch I'd do it before each section but if it's all garter stitch and increases just try to remember every couple inches to save frogging all your hard work.
Note: I can't fix increases, decreases, yarn overs etc either lol 
I use them on mitts after the cuff (if lace/cabled hand), and each pattern repeat (if lace/cabled) or before the thumb incase a mistake is made in the thumb gusset. I don't tend to after the thumb but there is no reason you couldn't if worried :)
I don't tend to use them on hats but sometimes do if they have quite a bit of patterning in them, same with cowls etc. For example I insert a life line after every lace repeat on the gothic lace cowl but don't tend to in the honey cowl or handbrake cowl.
I hope this was helpful :)
Happy Crafting!