when I travel solo I always have my phone with me, I text people what I will be doing on the day, at what time, and at what time I will be back, when I am back from my activities I will notify them...
So what I am trying to say, is if you want to travel solo, go book your flights, hotels and everything you will need for the travel, and give a trusted person your travel plans, so if something goes wrong, you will always know that someone is looking out for you.