1) Use wired instead of wireless
2) Get a faster internet connection
3) watch off peak hours (not needed with FTTH)
4) Drop ISPs that share bandwidth (most cable co.) and get an ISP with dedicated customer bandwidth (most FTTH providers)
TheTick
Roku 3 for Pokémon TV / YouTube / Animal Planet GO / HBO MAX. Chromecast for most other media because Roku Mirroring sucks , how many clicks in Wndows 10 (about a dozen) to Miracast on Roku vs 2 with Chromecast.
Verizon FIOS TV and Internet Service