I now only need to do mine once a year, and this is on a hot sunny day! I always put food into fridge for a few hours before placing in the freezer and this does really help with ice build up.
By closing the door as soon as you have taken out what you need and not leaving it open any more than needed you won`t have to de-ice more than necessary, and keeping it as full as possible also helps. This info applies to upright types only.