I've been in this trade officially for 5 years.
Nowadays I feel I can call myself a professional Illustrator, even if it's simply for the amout of work I've been pulling and for the kind of clients/gigs I've been getting. This is kind of a dream come true, and kind of because actually I never dreamed of becoming an illustrator, but I'd LOVE to do this full time for a living. But there is a minor problem... sometimes I'm rather unprofessional in my illo jobs... specially on those for private (non-publisher) commissioners.
Having two professional jobs (dayjob and illo work) is a bit complicated, specially since the average day only has 24 hours. When I started this as a job (aka started charging for drawing), I grabbed everything that came my way, and even actively went looking for work, and this quickly became an issue because even without much responsability in my hands there wasn't enough time in my day to pull out all the work in time. This went on for a couple years and a few commissions started to pile up... Then the professional work started to get more serious, and I started to get bigger jobs and even a couple crazy ones and grabbed less and less private commissions, but the "biting more than I could chew" issue still remained.
By the end of 2012 I realized (as obvious as it was) that I could't keep working like that or I'd be in serious trouble. I pretty much stopped grabing private commissions for the exception of a "once a year list", and even so I couldn't keep up, yet for financial reason I continued grabbing professional work instead of honoring full time the delayed commissions I had.
Around the middle of 2013, I realized that I needed to stop taking all work that came in or else I'd never deliver anything on time or at least deliver the overdue private stuff I owed, some of it even for years now... This epiphany came a bit late, and even thou I stopped taking private commissions and started declining a few pro jobs, The overdue pile was so big that I just couldn't make everyone happy anymore, or at least not too upset... I had to do some serious damage control (and a couple refunds...) and I'm still doing it to this day. By the end of 2013, I had a few professional contracts running and still a long line of overdue private commissiones. The biggest issue of 2013 was that I landed one of my biggest clients and that meant a LOT of work, and thus delayed my whole "production line" again, but it was one of those opportunities yu can't turn your back on, even if it mean lots more trouble.
And so starts 2014. I have a very short line of professional WIPs and still a long line of waaaay overdue private commissions. The year looks very promisiong since I had very little pro work to do!!!... Then life happens. Family stuff hits hard (a HUGE baby delivery drama) on february and it demands 101% of my time, and what little time I can steal for commissions must be focused on professional work (lest I lose a couple of my biggests accounts) and then I chip away painfully slowly the private commisions while juggling professional work and a very stressing life period. This went on until a couple months ago. Nowadays all is in relative order but my newborn baby still requires a bit more attention than the average infant does because of constant hospital visits. The professional work queue is down to a handful of clients and the private commission line is slowly starting to move.
My current schedule is like this: 90% of the work I've been posting the past couple months are gigs that I finished several months ago (some are form last year). I've stopped looking for work for over a year now, thou I've not turned away all the people who have come knocking and the only proffessional gigs I've grabbed are those form old time friends or those that pick my personal interest, and these are still within the "handful" (5 or less) of professinal projects runnig at the same time, with 4 of those due to be completed by early september. I've contacted most of my long overdue private commissioners and I'm working on a schedule with them. I'm yet to contact a few of the longest overdue commissioners, and that's because I want to compensate them big time for beign soooo patient and for that I need all the time I can muster to make some truly awesome stuff.
I'm all set and ready to use the rest of the year to do nothing but clearing my line of work and deliver ALL due work!
PS: Sorry for the extremely long rant, I needed to get this off my chest!
PS1: The lesson here is DON'T book more stuff than you can handle in proper time!