[RustysMom]

Hi,
I will answer based on my rescues. Each doggie is different, each with their own hurts, bad memories, etc. First, I learned the dog. I learned it's personality, it's needs. I asked nothing and didn't expect to teach it anything. I was learning from them. Building trust is key. You can tell a "kennel dog" from a home raised doggie. A kennel or cage dog has a fear of people. After the trust was built then I started slowly teaching a little bit at a time.
Journaling is very good. You can look back and see what you tried, what didn't work, what did.
For a harness, what the previous poster said was great. Put it on, leave it on, let them get used to it being there. Have extras in case they bite through them. They will.
Always speak in a calm, reassuring voice, never looking them in the eye. Do not laugh or show your teeth. Sit beside their crate or X-pen and read outloud etc., so they will become familiar with you and your smell.

For outside walks, take them alone, walk slowly, go to the same place. They will buck like a bronco trying to make that harness go away and try to get free. Speak calmly and keep moving forward.

It will take months. It takes quite awhile to build trust between you and them. But you will find that taking the time to build the trust will make then close to you and they will try so hard to perform things you want them to do, and then they will accept treats, enjoy walks, etc.

Love them. Never show anger with them.
They will learn your ways in their own time. You can't rush it. I never could anyway. I once kept a pair of maltese sisters almost a year. They were "kennel dogs". Had never been outside their cage.