Blisters can be caused by a number of factors including ill-fitting socks or shoes that don't fit right or are not appropriate for your needs. There are a few tips to avoid blisters: Introduce new running shoes gradually; There are specialist socks on the market with a double layer. The second layer stops the first one from rubbing against the skin; Try using petroleum jelly on areas prone to blisters. This helps the material glide over the skin, reducing friction.; Try using zinc oxide tape on blister prone areas to prevent friction on the skin. Experts recommend not popping blisters unless you absolutely have to. Protect with a 'second skin' blister plaster until the fluid dissipates. If you do pop a blister, make sure you use sterilized needle. Make sure the needle pierces as little as possible just to let the fluid out, and clean the area thoroughly, dressing it for at least 48 hours afterward to protect.