There are specific tools available on the Internet for sending newsletters and other types of email marketing. These tools comply with US regulations related to the sending of commercial email. They are offered by reputable vendors that are recognized as legitimate email marketing firms, so messages sent by these tools are much less likely to be flagged as spam by your subscriber's email providers.
SILO hosted email accounts are limited in the number of messages they can send per minute and the number of recipients that can be included on a single message. These limits are enforced to prevent spammers from abusing a single account to send out hundreds of messages at once which would get the SILO email server blacklisted for sending spam. These limits don't interfere with typical email, but they do prevent the accounts from being used to send newsletters to a large number of subscribers.
Guide
TinyLetter is a free newsletter service offered by the email marketing firm MailChimp. The service supports up to 5,000 subscribers on a single account. To use TinyLetter you'll need to create an account on their system.
After you've created an account, you'll want to update your profile. Under your account menu in the upper right corner, select the Your Profile option. Update the First and Last Name field. This is the name your newsletter subscribers will see in their email.
There are several help guides posted online that describe how to use the TinyLetter service.
Additional Options
There are a number of email marketing services available on the Internet. Some offer free service for a limited number of subscribers, while others offer a time limited free trial. If your newsletter requires additional features, search the web for recent reviews of email marketing services.