How can I install xclip on an EC2 instance?

Use

sudo amazon-linux-extras install epel -y
sudo yum install xclip -y

Source: https://gist.github.com/kevin-kientopp/7a1dee73ab0f1bdb21fe158407a028ea

You don't need xclip. Just ssh into the EC2 instance and cat the key to your terminal, then copy and paste it from your terminal to wherever you need it.

I needed this today for a file larger than a ssh-key, and cat was not enough. You need to enable the EPEL repo in EC2 in order to get xclip:

wget https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
sudo rpm -ivh epel-release-latest-7.noarch.rpm
sudo yum-config-manager --enable epel
sudo yum install xclip -y