Well there is a lot to that question we'd like to know before answering (like what kind of amp and cabinets you're useing etc.) But I'll give it a go. Please forgive me if my explanation is too basic.

The MOST important step in recording electric guitar is to get the amp sounding the way you want in the room first. It is EXTREMELY difficult to make something that sounds nothing like Steve Vai to begin with sound like Vai at mixdown.

I often use a combination of close mics and room mics and then combine the 2 at mix. For close mics I often use a dynamic mic. The standards for those are the Shure SM57 and the Sennheiser MD421. The 421 will sound a bit beefier on some amps but sometimes the 57 sounds better. It just depends and if you have the resources you can use both! If I had to buy only one of those mics I'd probably go for the 57 because you can use it on almost everything (including other instruments). It is VERY important to experiment with positioning when close micing a guitar cabinet. Moving the mic a few centimeters can make a huge difference. You should experiment with how close the mic is to the cone. Also play with how close the mic is to the center of the cone as opposed to the edge of the speaker. You should also experiment with the angle of the mic. On and off axis response will be different. Sometimes I'll have someone move the mic around while I listen and direct them from the control room. You can also listen through headphones while you're moving the mic around looking for the sweet spot. Remember, you also don't have to use a cardioid dynamic mic for close micing. Try out condensers and multiple pickup patterns too.

The next step I'd suggest is a room mic. Again this step requires a lot of experimenting. I will often use a large diaphragm condenser mic for the room, but again, there are no rules! You shold experiment with placement. Try starting 2-3 meters back from the cabinet. You can also try facing the mic away from the cabinet to get more of a room sound. Also try an omni pickup pattern. Remember that getting the room mic too close could cause phase problems. You may also want to experiment with stereo micing techniques for you room sound.

At mixdown when combining the 2 signals remember to check whether or not one of the signals should have its phase inverted. You can experiment with delat especially on the room mic. I will often mix in a few milisecond delayed version of one of the tracks to thicken the sound. You can also experiment with panning. Some people pan the room to one side and the dry close mic to another. You can also try panning a stereo room sound hard left and right and the dry close mic down the center.

There are SO MANY variables it's difficult to cover all of your options within a single post. I hope this helps you get started though. Good luck and remember the most important part is to HAVE FUN.

Bob

Bob,,thank you for your help.
I will follow your advice.
The amp that I have is jcm 900 and 800 and a preamp jmp1 of Marshall.
The mics that I have son:sm57,sm58.421,u67,u87,112,451,4050 and 414.
I am recording in Protools and I have some external processors.
If you are happened some other idea I would like to know it and if somebody more can help me I will thank it to him.
Thank you..

There is no right answer, except to experiment with rooms, amp choice & placement, mic choice & placement, and mic preamps to find the sound that you want. Hopefully, your own sound.

About mic placement...my best results often come when I use some inspired intuition and throw the mics up quickly.

Don't get too precious about it. Just throw 'em up and do it.

Jon

I'm sure everyone knows this, but as a fellow newbie let me add my two English pence:

I always find it worthwhile to mic up the strings of the electric guitar in addition to the amp. This means that I can mix back in the attack-only sound of dry strings, especially if the guitarist has opted for rather more overdrive than is really called for by the mix.

Originally posted by Martin Turner:
I'm sure everyone knows this, but as a fellow newbie let me add my two English pence:

I always find it worthwhile to mic up the strings of the electric guitar in addition to the amp. This means that I can mix back in the attack-only sound of dry strings, especially if the guitarist has opted for rather more overdrive than is really called for by the mix.

I agree with Martin, noting that this technique is especially effective on strummed/chordal rhythm guitar tracks.