Contact BotFather on Telegram (https://telegram.me/botfather) via private message and write the '/newbot' command. BotFather will ask you for a name (anything) and a username (globally unique). In return you will get an API token, looking like this:
110201543:AAHdqTcvCH1vGWJxfSeofSAs0K5PALDsaw
This token is used to authenticate requests to the bot API.
Automated build on Docker Hub is available.
docker run -i --name googleimagebot stanislavb/telegram-googleimagebot 110201543:AAHdqTcvCH1vGWJxfSeofSAs0K5PALDsaw
Handy instructions are in the Makefile.
make build
TOKEN=110201543:AAHdqTcvCH1vGWJxfSeofSAs0K5PALDsaw make run