Just stick with the regular safety basics.
1 - Making a web browser SPECIFICALLY for your crypto stuff (MEW & Exchanges).
2 - I personally login to MEW by copy / pasting their link which i saved already in a TXT file.
3 - I check their security certificate before entering my private key or JSON file (which is safer).
4 - I never click a link that says MEW is asking for this or that bullshit because it's 100% phishing URL.
All of that is great but it is useless if your operative system is full of viruses, if you are using windows you need to install an antivirus, an anti spyware and a firewall and you need to avoid installing suspicious stuff, it is a difficult battle to keep your system clean but you need to do it, but another option is simply to install a safer operative system based on Linux and forget about most viruses forever. 1 - Making a web browser SPECIFICALLY for your crypto stuff (MEW & Exchanges).
2 - I personally login to MEW by copy / pasting their link which i saved already in a TXT file.
3 - I check their security certificate before entering my private key or JSON file (which is safer).
4 - I never click a link that says MEW is asking for this or that bullshit because it's 100% phishing URL.
many people are not good people at the time so always be careful because they do not sleep to victimize people so always be careful .. my advice is to use your json file to not open your account and do not use the your private KEY because they are easier to open your account. 
