使zsh安装到$HOME/bin目录下：

wget https://www.zsh.org/pub/zsh-5.8.tar.xz
tar xvf zsh-5.8.tar.xz
cd zsh-5.8
./configure --prefix=$HOME/
make && make install

将zsh所在目录添加到PATH中，并设置zsh为默认shell：

在主目录下的.bash_profile或.bashrc中添加如下代码：

export PATH=$PATH:$HOME/bin   # 添加PATH
export SHELL=`which zsh`      # 设置$SHELL为zsh
exec `which zsh` -l           # 设置登录为zsh

安装Oh My Zsh

sh -c "$(wget https://raw.github.com/robbyrussell/oh-my-zsh/master/tools/install.sh -O -)"

如果网络受限，手动安装：

git clone git://github.com/robbyrussell/oh-my-zsh.git ~/.oh-my-zsh
cp ~/.oh-my-zsh/templates/zshrc.zsh-template ~/.zshrc

参考资料

http://ijinjay.github.io/blog/2016-04/%E9%9D%9E%E7%89%B9%E6%9D%83%E7%94%A8%E6%88%B7%E5%AE%89%E8%A3%85zsh%E5%92%8COh-My-Zsh.html