I planned to buy some altcoins now that we are in a bear market but someone I knew is telling me not to, that its possible more dumps will take place, my question is how will I know when it's the right time to buy coins?
The right time to invest is still there but the right time has passed some time ago. Since you are expressing your interest to invest, of course you can invest from here as the market has come down a lot. But while investing you must think about always investing in high ranking coins. Always invest wisely when you invest, especially in altcoins. And if you invest in the coin that has the best coins then your investment will be considered much less worthwhile.