You have two choices...
The wireless way:
SJ4000 WiFi has a built-in RTSP streaming server, supporting one client at a time with a limited resolution at 640x360.
This can be viewed locally by connecting your phone or laptop to the camera's access point, start a RTSP+H.264-capable media player (e.g. VLC Media Player), and instruct it to open following URL:
However, if you would like to allow multiple people to watch the stream, you would need to install a live streaming software (that supports RTSP video source) on your phone or laptop.
- VLC Media Player (at least the desktop version) can do a self-hosted live streaming in this scenario, but is awkward to set up.
- Open Broadcaster Studio is known to support this configuration as well as broadcasting into services like YouTube, Twitch, or Dailymotion.
The wired way:
SJ4000 WiFi is capable of acting as a USB webcam with HD-ready 1280x720 resolution.
Once the camera's USB port is connected to laptop or OTG-capable Android phone, choose "PCCamera" mode on camera's screen; and you can view the stream locally with any webcam application.
As you are going to re-broadcast the stream, any live streaming software should work (anything ranging from Google Hangouts, LINE, Facebook Live, Youtube app, to specialized ones like Open Broadcaster mentioned above).
As far as I have tested with my firmware version, the camera does not provide audio streaming in both RTSP and USB webcam mode. Since you are broadcasting sport event, you would have to insert live audio on-field in the live streaming software (optionally, with proper A/V delay compensation). Which in this case, the wired way is recommended, as there are more choices on software you can use.
If you are not particularly picky with the 0.6+ sec A/V desync, using wired mode with video chat applications mentioned above should suffice; they will pick audio from laptop/phone's microphone. However, if you need A/V delay compensation, use Open Broadcaster Studio or other specialized live streaming software of similar ability instead.
Hope this helps.