We recently discovered this great free alternative to Skype which doesn’t need to be installed on your system. You can access it directly on the web at https://whereby.com. You can have video conversations with up to 4 people at once and guests to your “room” don’t have to register to join in.
It takes less than a minute to create your room and share the link with someone you want to join you for a video chat.
I suggest you “claim” your room by registering; this allows you to “lock” your room to stop non-invitees from joining; it also reserves the room for you so that no-one else can claim it. There’s lots of information on their site but essentially it’s a very quick and easy process.