You can send an SMS message to a contact,

Send it from the contact’s profile page

Enter the contact’s name in the top search bar and select their name
You arrive on the contact’s profile page. (Other ways to get to a contact’s profile page)
Click Actions in the top right corner
A dropdown menu appears
Select SMS
You arrive on the SMS Conversations page for that contact
Enter your message and press Send

Send it from the Messaging App

Select the envelope icon in the top menu
You arrive on the Messaging page and the Colleagues tab is preselected
Select the Contacts tab
You arrive on the SMS Messaging App’s Conversations page
To view a conversation between your organisation and one of your contacts, you must click their name on the left
This displays your conversation history with the messages you have sent them on the right and their replies on the left
The top right corner of the page displays your organisation’s unique Makerble Mobile Phone Number
The left column lists all the contacts for whom you have a mobile number saved in one of the designated mobile number Contact Form fields
Select a contact on the left column to see their SMS Conversation history with the organisation appear in the right column
At the bottom of the right column is a text box which you can use to start typing an SMS message to that contact
Click the Send button to send the SMS
Any replies which the contact sends will be displayed in this pane
Any bulk messages that are sent to contacts including this contact, will also appear in the SMS Conversation history of that single contact