Hi Mae, I don’t know what software you are using to write music,(I use Nuendo 3.0) But the key to making all your songs the same level is firstly mix them one after another without changing your volume level. Then in the Mastering stage, use a good compressor to squash the valleys and peaks. If you are using Vegas, the same applies. I believe a compressor is included in the Sony plugins, with the Vegas install. Not certain though, as I don’t use it. Personally I really like the URS and Waves VSTplugins! Both have excellent compressors. Hope this helps a bit?