While working a blended desk may sound easy in theory, it takes a special person to do it effectively.  Not calling myself special...I left the last company that had me doing that...but the "wheel of fate" has spun and put me right back in it at my current company.  It may be temporary, it still will make my hair line recede.

Here are some tips that may save you if you ever get put into this position (someone leaves, like your sales guy or manager...etc.):

Organization

This is key.  If you start forgetting who the clients are and who the candidates are, you may get caught having an awkward conversation.  Keep your resumes, ad calls, job descriptions, and any notes well organized so you can be quick an on-point for when the call comes in, or when you make the call out.

Time Management

Obvious.  You have to make sure your schedule is packed everyday, and it needs to be structured so you can get the right things done at the right time (Sell during peak hours, recruit during non-peak hours). Your time is priceless...and has to be managed so that you can not only get the most out of a day, but also make all the time count...being you are the entire team. This goes into the next category....

Planning

Again, obvious.  I keep saying that though, and see so many people not do the obvious...  You need to make sure that you take the time to plan out a day, because you want to target the people who will buy from you, and the only way to do that is to take the time to find the companies that both utilize your services and want the candidate you are selling.  Without having this step, you could be wasting entire days of work.  I'll put it into perspective...we just had a nationwide competition where our upper management forced people to come up with competitor target lists (kill boards) and then market to them by email, followed up by phone calls the next day.  We pulled in, nationwide, 22 direct starts, 152 new job orders, 244 client visits, and 46 new leads that led to a job order.  That is not our typical day.  They then used this to show us that planning is extremely important.

Qualifying

You must do this effectively or else you won't be in the recruiting business long.  As both the sales and recruiting team, your time is priceless (as noted above), so you have to have good qualifying skills so you are not wasting your time on orders that won't close, or orders that take a serious amount of time.  "We take our time hiring, and will go through 50 candidates per opening before making a decision." Yes, I have heard that, and yes, I passed on that.  Companies that feel the pain can hire fast, and those are the ones that you should target.  Same thing goes on the recruiting side...you have to make sure the candidates you bring in can do the job or else you will have the metaphorical "egg on your face".  Urgency and good recruiting go together like peanut butter and jelly.  It just gives you good results!

All this being said, you have to keep in mind this is a lot of work.  It takes dedication, discipline, and energy to get the results you need.