It's nice to meet you! Summoning demons is a nasty business, if I was you I would start by summoning more neutral entities, such as natural spirits. From there, I would gradually move to the dead, then lesser angels / or demons. I would not advise ever working with the more powerful ones, only because we are but specs, worth nothing to them.
I guess I should explain a bit: There are two types of summoning: Invoking and Evoking. Invoking is asking the spirit into your own body, which is more dangerous and can lead to possession. Evoking is the art of bringing it forward through a channel outside of the body.
Overall a summoning spell most commonly has these parts:
Casting a circle, protecting the caster, cleansing the circle, cleansing the caster, creating a separate circle (for the spirit if you are evoking), and a channel for it to come into (again evoking), an opening rite, a connection (mental) or portal, a calling (there may be many), A rite of tongue (so he comes in a form you understand, and speaks in english) a cursing (if he doesn't come), a banishing if he is disobedient, and a respectful closing if he is obedient.
This is the relative parts, and each in their own could be considered a different spell.
This is just a rough overview, and it is not nearly as simple as others would have it. :) If you want some good texts, read the Solomonic Keys (aka: Goetia) or the book linked below. Hope this helped!
**I have issued general information only because this type of practice is HIGH magic. Please start with simpler spellcraft (low magic) before continuing to that more complicated**