Hi, it quite depends on your goal.
If you are looking to reach out to your potential clients in your niche and to grow your network, definitely check out LinkMe Tool - chrome extension that automates invitations and followup messages, so you can focus on establishing a relationship with the right people who are interested.
With the tool you can personalize invitation message and setup how many followup messages to send as well as when to send them. The messages will be sent to those who connected but didn't reply (on the date of the scheduled followup).
It can also track statistics of sent/connected/responded for you, so you can see how your campaign performs and to optimize it if needed.