I bought my husband some personalised socks with his first name already embroidered on them when he was in an assessment unit for a few months. It worked well because he had an uncommon name. Probably not cost-effective in the long run, but it solved a problem at the time. I am not good with needlecraft but I think going forward I would have gone down @Elle3 's route and had a stab at embroidering his initials on to his socks.