SMS Gateway Setup
You will need any Android or iPhone device that can make calls and send SMS messages, so SIM card should be inserted and phone should be active all the time.
Step 1: Install to mobile phone
Install PushBullet application from Google Play or from iTunes
Sign in using the Google or Facebook account.
Step 2: Setup API KEY
Sign it to Pushbullet web site with your Facebook or Google Account
Select Settings -> Account and then click on Create Access Token
Copy this value and send to firstname.lastname@example.org
Step 3: Setup Encryption
Select Settings -> End To End Encryption and then click on Save button
Send this password to email@example.com
Step 4: Setup Encryption (Step 2)
On your device run pushbullet application and open the settings menu.
From the setting menu select Encryption and type password there.
Step 5: Setup SMS text
From Basic Package, settings select SMS Templates in the menu. Select language and define SMS message as you need.
Setup call forward (Optional)
If you want to answer your clients from different than this phone, use standard phone network feature like Call Forwarding.
Step 6: Verify SMS messages are sent
In order to verify what messages were sent out, open standard Messages application on your phone, and you will find all sent messages there as if you type and send them yourself.