A) Setup (1 time only)
1) gpg --gen-key

2) add to ~/.rpmmacros
    %_signature gpg
    %_gpg_name <your name> <email>

3) gpg --export --armour keyid > <file name> i.e. RPM-GPG-KEY-bchao
            --keyid = <email>

B) Create Repository

1) create accessible directory
/var/www/html/<directory name> i.e. bchao

2) Put packages in that direcectory

3) rpm --addsign *.rpm
    --rpm -qip <rpm package> checks for signature

4) createrepo .

C) Create .repo file

1) put gpg public key* in /etc/pki/rpm-gpg/
*From Part A step 3

2) create .repo file in /etc/yum.repos.d