Wasn't really sure of the best section for this but this one seemed to fit best?
When I returned to the fold last year after a long break I discovered that online sites like qrz.com were most definitely 'in'. None of these online searches and logbook sites were about when I was last active so I had a bit of a learning curve to find the best way of doing it.
Here in the UK with the required (and preferred by me) signing of /P for portable operation and the addition of a country identifier into the callsign, it meant I am commonly operating under 3 callsigns:
My chosen logging software was the free Log4OM and exploring it's abilities I could find ways to accurately log all activities at the right place and right callsign. I then needed to set up the online sites to suit, which was not always that easy as most of them are US based and adding a W into the middle of my callsign was not something the system was set up for easily (support can do it).
Anyway I solved all the issues and was successfully logging my activities and I started to get a few emails coming in asking how I had achieved it.
The answer was really with a fair bit of poking about and head scratching, so it appeared others were in the same boat. This prompted me to add a series of pages to my radio site to help others get things set up for portable operation logging.
The link below is the first page of the series that specifically deals with Log4OM (which by the way I do recommend as a free option for logging) but at the bottom of that page is a link each to how I set up the main online sites like qrz.com, eQSL, LoTW, hamQTH, clubLog etc.
Hope it helps.