use the notification card to allow the sdcard to be mounted
drag the apk file onto your card...doesn't matter where but I made an APK folder on mine
go back to the notification bar and unmount the card.
In settings-applications you need to allow Unknown Sources to be installed on your phone.
use Astro, free app from the market, to navigate to /sdcard/apk and select the file. It will let you open it in the app manager and then you can install it.
To install APK applications on your Android phone do the following:
1. Copy the APK file you want to install to your phone's memory card.
2. Go to Android Market and search for the Apps Installer application.
Open it and click on the Install button.
3. After it is installed, just open it. It will show you all the APK files stored directly in the root directory of your memory card.
4. Just click on the application you want to install and it will be installed.
or
1. Download the app.
2. Transfer the app to your phone and place in a folder you will remember placing it in on your SD Card (Skip this step if using you Android to download).
3. Go to the Market (on your Android) and search for Astro.
4. Download Astro File Manager (its free).
5. Once installed open Astro.
6. Go to the folder you put the application in (if you downloaded from you Android it will be the folder call "download" or "downloads").
7. Click the app once (a Pop Up should appear) and choose open app manager (or words to that effect).
8. Click install once (you may get a Pop Up saying its blocked from installing just go to the settings and check the "Unknown Applications").