Output Settings: container should be set to MP4 and tick the box marked "Web Optimized"
Go to the Video tab, select:
Codec- h.264 (x264)
Quality: Select average bitrate and in the text field enter 900
Also select 2-pass encoding & turbo-first pass.
Select the box Use Advanced Tab instead under Optimise Video
Go to Audio tab & select audio tracks & quality, it should be about 128 Kbps
Now go to the Advanced tab. If you do not see this tab, enable it by going to Tools > Options > General and ticking the box "Show Advanced Encoder Options Tab" under User Interface.
Once you have the Advanced tab enabled, use the following settings: