We receive a lot of questions about how to use 8F to do stuff. Sometimes these are very complex questions that requires some knowledge regarding opcodes, but sometimes, as it is the case with your request, you don't need to know much. This knowledge is already available here and elsewhere in the form of ready-to-use, well-explained setups in which you only have to change a few things using tables and lists that we also give and explain.
Although we are here to help people discover this glitch and how to use it, I would like to mention to you and all the others that will come after, that if you just read what is already available, you can already answer your question. In fact, I strongly advise you to document yourself about 8F before trying to do it, even if you just use a code that someone gave you. It is always better to understand what you do to use it the proper way.
Thus said, here's one answer to your question.
To get the 8F item, you can use the celadon loop as described here: http://forums.glitchcity.info/index.php?topic=6638.0
As a proper Pokémon setup, you can use this: http://glitchcity.info/wiki/Arbitrary_code_execution#Using_8F_.28English_Red.2FBlue.29
Now, select the RAM address you would like to change using, for example, this list: http://datacrystal.romhacking.net/wiki/Pokemon_Red:RAM_map
Here, let's say you want to change the letter 1 of your first Pokémon's nickname. This is address $D2B5
Now, select the value you want to put in it using, for example, this list: http://glitchcity.info/biglist.htm
Here, let's say that you want to change that letter for the number "4". As you can see, it matches hexadecimal $FA
(On a side note, understand that what you are about to do is asking for $D2B5
to take the value $FA
. As a result, this corresponds to using the gameshark code 01FAB5D2
To trigger the 8F code, use this item setup. It's a generic setup for one-value changing codes:
- Any item at any quantity
- Lemonade xAA
- X Accuracy xBB
- Carbos xCC
- Poké Ball, x119
- Fresh Water x201
AA, BB and CC are decimal translation of the three red, blue and green values (your RAM address and the value to give to it). You can translate hexadecimal to decimal with the windows calculator, or just the abovementioned list (http://glitchcity.info/biglist.htm
). Here, it says 250
Once you're ready, just use the 8F item