Move your dog in gradually over several days vs all at once to prevent shock and shutdown. Take it slow.
Rushing the Transition
Slowly introduce your new dog to current pets and family members to prevent territorial issues.
Give your dog several weeks to settle in and build confidence. Have patience with initial quirks.
No Adjustment Period
Confine your new dog until potty trained and comfortable. Too much freedom too fast causes accidents.
Maintain the shelter's schedule. Slowly transition food and introduce change to avoid shocking the digestive tract.
Don't overwhelm your dog with meeting tons of new people and new places initially. Build up slowly.
Too Much Too Soon
Adopted dogs need more work and patience. Assume nothing and positively train desired behaviors.