I thought I usually have a few things going (altho sometimes most of them are 'going' in my head
) But after reading your initial post and several of the answers, I looked around my sewing room and realized that I do usually work on one thing at a time--unless an emergency like a quickly needed baby quilt or BOM intervenes. I also work better in a clean (well, more or less--if it was totally clean, it wouldn't be mine!) sewing room. A few things that I do:
Before starting a new project I tidy my work space as much as possible. I try to keep only the necessary tools, fabric, rulers and pattern on my table. And having read that sentence again, I realize that, what has been bothering me for the last two days is, that I am not using my usual cutting space. I will rectify that tomorrow.
Bobbins!! Zozee had it right. I try to fill a couple or three bobbins at a time because an empty one can be as bad as a cow on the railway tracks! Taking the time to fill at the end of a day really really helps!
I find repetition can also be a mood killer. Since my current project has four specific steps, I broke it down. I need 32 strip sets of 6 fabrics. 1. cut the strips for 11 strip sets 2. sew and press them 3.cut the necessary shapes from them 4. sew the shapes into rows and press. Repeat. I will assemble the quilt once all the rows are completed.
I do have some UFO's. One was supposed to be a QAYG reversible quilt (and may still end up that way) but I do not think I have the skills to quilt each block as I envision. Another is just missing the final row. It was done at a retreat and I ran out of fabric. By the time I got more, the Muse had moved on. And the final is an idea--fabric, drawings etc all put into a tote until that pesky Muse decides the time is right.
I do have a couple--well, three--projects that are on-going. One is hand pieced hexies. I have not been as diligent at working on them as I should, but they are a great portable project. The second is a challenge put out by my sister--Anita's arrowhead blocks--but my vision of the finished project has mushroomed. The third is 9 patches using scraps. The last two projects are 'fillers'--when I don't have anything else really going. They will get to where they have to be eventually, and I am happy with that.
Thanks for wading thru all my meanderings and I hope that you found a kernel or two of wisdom within, that will help you.