The way you handle your bird in the field will effect how it looks when it is mounted.
Handle the bird by the feet. Put it in a plastic bag, preferably a Ziploc or a trash bag and seal it. Put the bird in the freezer and keep it frozen until it’s taken to the taxidermist. If the bird will be in the freezer for a while, then after the bird is in a plastic bag, wrap the bird in newspaper or butcher paper to prevent the feathers from getting damaged. Broken or damaged wings, feet, feathers, and bills can all be easily repaired. Muddy or bloody feathers are no problem at all.