Internet speed and stability are the lifeblood of online tutors, and any professionals who rely on real-time communications more generally. Poor internet means poor service delivery, which means poor client retention on Spires.
To begin with, you need to invest in a good high speed internet connection, ideally a full fibre connection. Get the best available, it's a good investment. Fibre supports the highest and most reliable speeds, where as many people will be getting their "broadband connections" through ADSL cables - their telephone line. ADSL connections are the most prone to slowing down when there is a lot of internet traffic, i.e. between 4-7pm everyday, also the most popular time for tutoring.
You may also want to consider 4G and 5G connections as alternatives/backups. You can either hotspot from your existing smartphone, but many companies will offer a secondary router also. 4G speeds will match some ADSL connections, 5G speeds are extremely high and can match fibre speeds.
If you have a good internet connection (stable and high upload/download speeds and pings - test), and still experience issues then most likely the issue is with your router or network card, i.e. your 'Wi-Fi'. There are several ways to improve this:
Change/replace your router - The routers that can come as standard from your ISP can have poor stability, especially older models. You can call the internet company and ask for a new model, or you can also purchase your own. It's an overlooked investment and if it gives you stable internet it's well worth the investment in time and money.
Weak signal strength - You could be too far from the router and will need to move closer, or consider a signal booster if you cannot practically be closer. There may also be things blocking the signal emitted by the router, the common causes are metal/water (radiators) and things that contain them, or other people's home networks in your area. Consider repositioning your router. If you know how, you can change frequency on your wi-fi via your router settings (2.4Ghz is better than 5Ghz for penetration), but this requires technical knowledge.
Too much interference - There can be other devices, such as cordless phones, microwaves and other Wi-Fi networks using the same frequency (channel) as your router. The solution is to change the channel, many modern routers will do this automatically, but you can do it manually and can contact the internet company to get help on this. There are apps on your phone which can scan the wi-fi and tell you if your channel is too busy.
Poor or broken network card - This happens a lot. They break and need replacing. It's a common source of network issues. Also worth investing in if you have a professional reliance on stable internet, which online tutors do.
You can also consider an Ethernet Cable, this is when you connect to the internet via a wire that links your computer to your router. It is the most stable and most reliable form of connection, the only draw back is that you have to be physically connected via a wire.