Schematic advice for a noob

[CaptainAmerica]

i would like to  have a circuit that when i press a button it turns a servo 90 degrees then when the button is pressed again the servo is returned to its original position. Or at the least a similarly functioning device any ideas? i have heard that this can be done with a 555 chip but i need some more info

[Hero999]

I don't know and nor will anyone else because you haven't said what sort of servo mechanism you're using.

[kxenos]

I would suggest that you start by picking a suitable servo for your application. After this you will probably want to select a driver IC suitable for your motor. In order to select the driver IC you will have to think about the system that will tell the servo to move. Is it digital? Like a uC? Is it something simpler like a user pressing a button?
When you start designing an application you start by the functional requirements. What do you want your system to do. The specs. After this you have to think about the non-functional requirements - if any. After this you start with a rough block design. I'm gonna have a block (a module, a circuit) that does this. An other block that does that, etc. You define the interconnection signals according to the requirements (mainly the functional ones) and the constrains. A requirement for example might be that you want to have fine control over the angle so you have to use a uC or CPLD and a feedback mechanism. A constrain might be that for example it's difficult to find ICs that drive the motor and have digital interface at a reasonable price for your budget. etc. And you go on like this, revisiting and improving your design until you feel that there is a fair possibility that it actually might work. You build it and then start debuging. muhahaha (satan's laugh!) Just kidding! :-) Really, starting is the half of it. Debugging is the rest!

Konstantinos