Can you suggest some precautions for beginners to avoid getting scammed ?
Avoid joining those double your bitcoin programs and Hyip's (high yield investment programs). Do not join those people telling that they will trade for you and double your bitcoin in days or weeks you will likely be scam by those people as i see many people posting it from bitcoin groups. Do some research or ask here.
I agree. If something is too good to be true, its more likely a scam. Hyips have a way to attract people who prefer easy money but if you want to try your luck there, reasearch. Look for facebook pages, scan through comments,threads and discussions. It's better to be safe than sorry. That's coming from someone who got scammed by joining a hyip and learned a bitter lesson