help with electrical problems 90 camry

it first started when i turned my lights on my radio would cut off....now if i do any thing such as turn on the blinkers or turn on the flip down mirror lights the radio cuts off, then my car would not start up and i just bought a brand new battery......any suggestions on what to do

Check out the charging system.

Check out the charging system.
What he said!
When you start your car, read the battery voltage. I do not remember the exact reading, but it should be something like 14.6 volts. If not - that is your alternator. If you do a search I am pretty sure you will find more information on this, as well as on how to rebuild your alternator if it is the problem.