Gmail
Open Gmail.
Go to https://www.gmail.com/ in your computer's web browser. This will open your Gmail inbox if you're logged in.
- If you aren't logged into your Gmail account, enter your email address and password when prompted.
Click ＋ Compose. It's in the upper-left side of your Gmail inbox. Doing so opens a "New Message" window in the lower-right corner of the page.
- If you're using the old version of Gmail, you'll click COMPOSE here instead.
Enter the other person's email address. Click the "To" or "Recipients" text box at the top of the New Message window, then type in the email address of the person to whom you want to send your email.
- To add multiple email addresses, type in the first email address, press Tab ↹, and repeat with the other email addresses.
- If you want to CC or BCC someone on the email, click either the Cc link or the Bcc link in the far-right side of the "To" text field, then type the email address you want to CC or BCC into the "Cc" or "Bcc" text field, respectively.
Add a subject. Click the "Subject" text field, then type in whatever you want the subject of the email to be.
Enter your email message. In the large text box below the "Subject" text box, type in whatever you want for your email message.
Format your email's text if needed. If you want to apply formatting to your text (e.g., bolding, italics, or bullet points), highlight the text to which you want to apply the formatting, then click one of the formatting options at the bottom of the email window.
- Typically speaking, an email subject describes the gist of the email's message in a few words.
Enter your email message. In the large text box below the "Subject" text box, type in whatever you want for your email message.
Format your email's text if needed. If you want to apply formatting to your text (e.g., bolding, italics, or bullet points), highlight the text to which you want to apply the formatting, then click one of the formatting options at the bottom of the email window.
- For example, to bold a section of text, you would highlight the text and then click B at the bottom of the email.
Attach a file if you like. To add a file from your computer, click the "Attachments" 
icon at the bottom of the window, then select the file(s) you want to upload and click Open (or Choose on a Mac).
- You can add photos in this way, or you can upload photos directly to the email's body by clicking the "Photos" icon at the bottom of the window, clicking Upload, clicking Choose photos to upload, and selecting photos as needed.
Click Send. It's a blue button in the bottom-left corner of the email window. Doing so will send your email to the specified email address(es).
You can use the Gmail website to send email from a computer, or you can use the Gmail mobile app to send email from a smartphone or tablet.