I tried that. download speed at 2.39 and upload speed was at 3.64. now how do i make it better
The speedtest results are meaningless without knowing what speed your package is. For example, getting 2.87 Mbps down on a 3 Mbps package is good, but it's absolute garbage on an 18 Mbps package. Also, there are other factors at play here that could impact your speed:
1. router configuration issues
2. Roommates hogging bandwidth
3. Automated backups to Time Capsule taking up part of the bandwidth.
What I would recommend doing (I work for an ISP) is to connect your computer directly to your cable/dsl modem and running a speedtest to see what the modem itself is pulling for speed. The download speed should be at least 80% of the rated package speed. Then I would reconnect the Time Capsule with ONLY your computer connected and run it again. If there's a big dropoff, then the Time Capsule needs to be reconfigured. If no change, then add the other devices.
This might also be an issue where the solution is simply to upgrade your internet service to a higher speed.