Mirror, mirror on the wall
Good advice: never shave in the shower with a straight! The shower is for the safety razor. Along with a cheap boar bristle brush, stick-on magnifying mirror, and a cake of Dove soap when those "no time for a straight razor shave" times occur. For a real straight razor shave the shower is where (after the washing part) you shampoo your whiskers and then lather up with the Dove bar. Use a hand towel as a wrap after it was previously wraped around the shower head (hang it down like a tube from the shower head and twist it at the bottom) while the water temp. is on hot as you can stand it. Once for the shampoo and then the Dove lather second. This really gets whiskers soft. Then I use a swing out mirror at the sink, but a folding magnifying mirror (which you can use for travel; I do) on a makeshift stand will work. Make it work for you; shaving while learning is hard enough. We all need to see clearly what we are doing.